Robotic medical systems with high force instruments

ABSTRACT

A robotic system can include a high force instrument that amplifies input forces such that output forces are greater than input forces. The high force instrument can include an end effector. The high force instrument can further include a first pulley configured to rotate about a pulley axis and a first jaw member connected to the first pulley by a first drive pin. The high force instrument can also include a second pulley configured to rotate about the pulley axis and a second jaw member connected to the second pulley by a second drive pink. A link can provide a first pivot point about which the first jaw member can pivot and a second pivot point about which the second jaw member can pivot.

PRIORITY APPLICATION

This application claims priority to U.S. Provisional Application No.62/682,049, filed Jun. 7, 2018, which is incorporated herein byreference. Any and all applications for which a foreign or domesticpriority claim is identified in the Application Data Sheet as filed withthe present application are hereby incorporated by reference under 37CFR 1.57.

TECHNICAL FIELD

This application relates to robotic medical systems, and in particular,to robotic medical systems with high force instruments.

BACKGROUND

Medical procedures, such as laparoscopy, may involve accessing andvisualizing an internal region of a patient. In a laparoscopicprocedure, a medical instrument can be inserted into the internal regionthrough a laparoscopic access port.

In certain procedures, a robotically-enabled medical system may be usedto control the insertion and/or manipulation of the instrument and anend effector thereof. The robotically-enabled medical system may includea robotic arm, or other instrument positioning device. Therobotically-enabled medical system may also include a controller used tocontrol the instrument during the procedure.

SUMMARY

In a first aspect, a robotic system includes an instrument having an endeffector. The instrument comprises a first pulley configured to rotateabout a pulley axis, a first jaw member connected to the first pulley bya first drive pin, a second pulley configured to rotate about the pulleyaxis, a second jaw member connected to the second pulley by a seconddrive pin, and a link providing a first pivot point about which thefirst jaw member can pivot and a second pivot point about which thesecond jaw member can pivot.

The robotic system may further include one or more of the followingfeatures in any combination: (a) a robotic arm coupled to theinstrument; (b) wherein rotation of the first pulley causes rotation ofthe first drive pin about the pulley axis, further causing the first jawmember to pivot about the first pivot point, and rotation of the secondpulley causes rotation of the second drive pin about the pulley axis,further causing the second jaw member to pivot about the second pivotpoint; (c) a geared constraint configured to constrain motion of thefirst jaw member and the second jaw member such that motion of one ofthe first jaw member and the second jaw member causes a substantiallycorresponding motion of the other of the first jaw member and the secondjaw member; (d) wherein the geared constraint comprises a cycloidconstraint, the cycloid constraint comprising a tooth formed on one ofthe first jaw member and the second jaw member, and a notch formed onthe other of the first jaw member and the second jaw member; (e) whereinthe geared constraint comprises a pin which extends along an axisthrough the first jaw member and the second jaw member, wherein the pinis configured to ride within a slot formed in at least one of the firstjaw member and the second jaw member; (f) a slot constraint configuredto prevent or reduce a risk of rotation of the end effector about thefirst drive pin and the second drive pin when the first drive pin andthe second drive pins are aligned; (g) wherein the slot constraintcomprises a first ear, a second ear spaced apart from the first ear toform a slot between the first ear and the second ear, and a pinextending along the pulley axis positioned within the slot; (h) whereinthe first ear and the second ear are each coupled to the link; (i) ageared constraint configured to constrain motion of the first jaw memberand the second jaw member such that motion of one of the first jawmember and the second jaw member causes a substantially correspondingmotion of the other of the first jaw member and the second jaw member,and a slot constraint configured to prevent or reduce a risk of rotationof the end effector about the first drive pin and the second drive pinwhen the first drive pin and the second drive pins are aligned; (j)wherein the first pulley and the second pulley can rotate to a positionin which the first drive pin and second drive pin are aligned; (k)wherein, during rotation of the first pulley and the second pulley, thefirst drive pin can rotate past the second drive pin; (l) wherein thelink comprises a housing comprising a first bearing surface spaced apartfrom a second bearing surface, the first jaw member comprises a firstgroove configured to pivot on the first bearing surface to form thefirst pivot point, and the second jaw member comprises a second grooveconfigured to pivot on the second bearing surface to form the secondpivot point; (m) wherein the end effector is configured as a grasper,cutter, or clipper; (n) wherein a first link comprises a first distancebetween the pulley axis and a point at which an input force is appliedby a cable wound on the first pulley, a second link comprises a seconddistance between the pulley axis and an axis of the first drive pin, athird link comprises a third distance between the axis of the firstdrive pin and an axis of the first pivot point, a fourth link comprisesa fourth distance between the axis of the first pivot point and a distalend of the first jaw member; (o) wherein the first distance of the firstlink is between 3 and 4 mm, the second distance of the second link isbetween 2 and 3 mm, the third distance of the third link is between 7and 8 mm, and the fourth distance of the fourth link is between 17 and23 mm; (p) wherein the first distance of the first link is approximately3.35 mm, the second distance of the second link is approximately 2.5 mm,the third distance of the third link is approximately 7.3 mm, and thefourth distance of the fourth link is approximately 20 mm; (q) wherein afirst ratio between the second distance of the second link and the firstdistance of the first link is between 0.5 and 1.25, a second ratiobetween the third distance of the third link and the first distance ofthe first link is between 1.5 and 3.5, and a third ratio between thefourth distance of the fourth link and the first distance of the firstlink is between 1.5 and 20; and/or (r) wherein a first ratio between thesecond distance of the second link and the first distance of the firstlink is approximately 0.75, a second ratio between the third distance ofthe third link and the first distance of the first link is approximately2.18, and a third ratio between the fourth distance of the fourth linkand the first distance of the first link is approximately 6.

In another aspect, a robotic system includes a medical instrumentcomprising an end effector configured to be inserted into a patientduring a medical procedure. The medical instrument comprises a firstpulley, a first jaw member connected to the first pulley, a secondpulley, a second jaw member connected to the second pulley, a linkproviding a first pivot point about which the first jaw member can pivotand a second pivot point about which the second jaw member can pivot,and at least one of a geared constraint and a slot constraint.

The robotic system may further include one or more of the followingfeatures in any combination: (a) wherein the end effector is connectedto a robotic arm and controlled by a processor of the system; (b)wherein the end effector and at least a portion of the medicalinstrument are configured to fit through a patient opening that is lessthan 14 mm; (c) wherein the end effector and at least a portion of themedical instrument are configured to fit through a patient opening thatis less than 10 mm; (d) wherein the end effector and at least a portionof the medical instrument are configured to fit through a patientopening that is less than 10 mm; (e) wherein the end effector isconnected to the distal end of the medical instrument by a wrist havingat least two degrees of freedom; (f) one or more cables connected to thefirst pulley, wherein pulling one or more of the cables connected to thefirst pulley causes rotation of the first pulley, and one or more cablesconnected to the second pulley, wherein pulling one or more cablesconnected to the second pulley causes rotation of the second pulley; (g)wherein the one or more of the cables connected to the first pulley andthe one or more of the cables connected to the second pulley extendthrough the medical instrument, the medical instrument is attached to aninstrument drive mechanism, and the instrument drive mechanism isconfigured to pull the one or more of the cables connected to the firstpulley and the one or more of the cables connected to the second pulleyto actuate the end effector; (h) wherein the end effector comprises thegeared constraint, wherein the geared constraint comprises a cycloidconstraint that is configured to constrain motion of the first jawmember and the second jaw member such that motion of one of the firstjaw member and the second jaw member causes a substantiallycorresponding motion of the other of the first jaw member and the secondjaw member; (i) wherein the geared constraint comprises a tooth formedon one of the first jaw member and the second jaw member, and a notchformed on the other of the first jaw member and the second jaw member;(j) wherein the end effector comprises the slot constraint, wherein theslot constraint is configured to prevent rotation of the end effectorabout the first drive pin and the second drive pin when the first drivepin and the second drive pins are aligned; and/or (k) wherein the endeffector comprises the slot constraint and the geared constraint.

In another aspect, a method includes inserting a robotically-controlledmedical instrument into a patient. The instrument including an endeffector. The end effector comprises (i) a first jaw member coupled to afirst pulley, (ii) a second jaw member coupled to a second pulley, (iii)a link connecting the first jaw member and the second member, and (iv)at least one of a geared constraint and a slot constraint; and actuatingthe end effector based on pulling at least one cable connected to thefirst pulley or the second pulley to cause rotation of the first pulleyor the second pulley, wherein rotation of the first pulley or the secondpulley opens or closes the first jaw member and the second jaw member ofthe end effector.

The method may further include one or more of the following features inany combination: (a) wherein actuating the end effector comprisescausing rotation of the first pulley and the second pulley such that afirst drive pin connecting the first pulley to the first jaw memberoverlaps with a second drive pin connecting the second pulley to thesecond drive; (b) wherein the overlap of the first drive pin and thesecond drive pin increases force amplification at the end effector; (c)wherein the end effector comprises the geared constraint, and whereinthe geared constraint is configured to constrain motion of the first jawmember and the second jaw member such that motion of one of the firstjaw member and the second jaw member causes a substantiallycorresponding motion of the other of the first jaw member and the secondjaw member; (d) wherein the geared constraint comprises a cycloidconstraint comprising a tooth formed on one of the first jaw member andthe second jaw member, and a notch formed on the other of the first jawmember and the second jaw member; (e) wherein the end effector comprisesthe slot constraint, wherein the slot constraint is configured toprevent rotation of the end effector about the first drive pin and thesecond drive pin when the first drive pin and the second drive pins arealigned; and/or (f) wherein the end effector comprises the slotconstraint and the geared constraint.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed aspects will hereinafter be described in conjunction withthe appended drawings, provided to illustrate and not to limit thedisclosed aspects, wherein like designations denote like elements.

FIG. 1 illustrates an embodiment of a cart-based robotic system arrangedfor diagnostic and/or therapeutic bronchoscopy.

FIG. 2 depicts further aspects of the robotic system of FIG. 1.

FIG. 3 illustrates an embodiment of the robotic system of FIG. 1arranged for ureteroscopy.

FIG. 4 illustrates an embodiment of the robotic system of FIG. 1arranged for a vascular procedure.

FIG. 5 illustrates an embodiment of a table-based robotic systemarranged for a bronchoscopic procedure.

FIG. 6 provides an alternative view of the robotic system of FIG. 5.

FIG. 7 illustrates an example system configured to stow robotic arm(s).

FIG. 8 illustrates an embodiment of a table-based robotic systemconfigured for a ureteroscopic procedure.

FIG. 9 illustrates an embodiment of a table-based robotic systemconfigured for a laparoscopic procedure.

FIG. 10 illustrates an embodiment of the table-based robotic system ofFIGS. 5-9 with pitch or tilt adjustment.

FIG. 11 provides a detailed illustration of the interface between thetable and the column of the table-based robotic system of FIGS. 5-10.

FIG. 12 illustrates an exemplary instrument driver.

FIG. 13 illustrates an exemplary medical instrument with a pairedinstrument driver.

FIG. 14 illustrates an alternative design for an instrument driver andinstrument where the axes of the drive units are parallel to the axis ofthe elongated shaft of the instrument.

FIG. 15 depicts a block diagram illustrating a localization system thatestimates a location of one or more elements of the robotic systems ofFIGS. 1-10, such as the location of the instrument of FIGS. 13 and 14,in accordance to an example embodiment.

FIG. 16A illustrates a side view of a high force instrument.

FIG. 16B illustrates a detailed view of a distal portion of the highforce instrument of FIG. 16A, showing additional detail of a wrist andan end effector of the high force instrument.

FIG. 17A illustrates an embodiment of a high force instrument in an openposition.

FIG. 17B illustrates the high force instrument of FIG. 17A in a closedposition.

FIG. 18A illustrates another embodiment of a high force instrument in anopen position.

FIG. 18B illustrates the high force instrument of FIG. 18A in a closedposition.

FIG. 19A illustrates another embodiment of a high force instrument in anopen position.

FIG. 19B illustrates the high force instrument of FIG. 19A in a closedposition.

FIGS. 20A, 20B, 20C, and 20D illustrate views of components of variousembodiments of high force instruments and further illustrate how thegeometry can be varied to adjust a mechanical advantage of a high forceinstrument.

FIG. 21 illustrates a perspective view of an embodiment of a pulleywrapped with a pull wire.

FIGS. 22A, 22B, and 22C illustrate views of an embodiment of a highforce instrument that includes a geared constraint configured as a pinbased cycloid constraint.

FIG. 23 illustrates a view of another embodiment of a high forceinstrument that includes a geared constraint configured as a pin basedcycloid constraint.

FIGS. 24A-24H illustrate views of an embodiment of a high forceinstrument that includes two constraints. FIG. 24A is a front view ofthe instrument in an open position,

FIG. 24B is an exploded view of the instrument, FIG. 24C is a side viewof the instrument, FIG. 24D is a back view of the instrument in an openposition, and FIG. 24E is a bottom cross-sectional view of theinstrument. FIGS. 24F, 24G, and 24H illustrate drive pins crossing asthe instrument moves from an open position to a closed position.

FIGS. 25A-25H illustrate views of an embodiment of a high forceinstrument that includes two constraints and a single piece link. FIGS.25A and 25B illustrate views of the instrument in open and closedconfigurations, respectively. FIG. 25C illustrates an embodiment of ahousing that serves as the link for the instrument. FIG. 25D illustratesa view of a first or second jaw member for the instrument. FIGS. 25E,25F, 25G, and 25H illustrate stages during an example assembly processfor the instrument.

FIGS. 26A and 26B are diagrams illustrating how mechanical advantage canbe determined for a high force instrument.

FIG. 27 is a graph depicting a force profile for one embodiment of ahigh force instrument.

DETAILED DESCRIPTION 1. Overview

Aspects of the present disclosure may be integrated into arobotically-enabled medical system capable of performing a variety ofmedical procedures, including both minimally invasive, such aslaparoscopy, and non-invasive, such as endoscopy, procedures. Amongendoscopic procedures, the system may be capable of performingbronchoscopy, ureteroscopy, gastroscopy, etc.

In addition to performing the breadth of procedures, the system mayprovide additional benefits, such as enhanced imaging and guidance toassist the physician. Additionally, the system may provide the physicianwith the ability to perform the procedure from an ergonomic positionwithout the need for awkward arm motions and positions. Still further,the system may provide the physician with the ability to perform theprocedure with improved ease of use such that one or more of theinstruments of the system can be controlled by a single user.

Various embodiments will be described below in conjunction with thedrawings for purposes of illustration. It should be appreciated thatmany other implementations of the disclosed concepts are possible, andvarious advantages can be achieved with the disclosed implementations.Headings are included herein for reference and to aid in locatingvarious sections. These headings are not intended to limit the scope ofthe concepts described with respect thereto. Such concepts may haveapplicability throughout the entire specification.

A. Robotic System—Cart.

The robotically-enabled medical system may be configured in a variety ofways depending on the particular procedure. FIG. 1 illustrates anembodiment of a cart-based robotically-enabled system 10 arranged for adiagnostic and/or therapeutic bronchoscopy. During a bronchoscopy, thesystem 10 may comprise a cart 11 having one or more robotic arms 12 todeliver a medical instrument, such as a steerable endoscope 13, whichmay be a procedure-specific bronchoscope for bronchoscopy, to a naturalorifice access point (i.e., the mouth of the patient positioned on atable in the present example) to deliver diagnostic and/or therapeutictools. As shown, the cart 11 may be positioned proximate to thepatient's upper torso in order to provide access to the access point.Similarly, the robotic arms 12 may be actuated to position thebronchoscope relative to the access point. The arrangement in FIG. 1 mayalso be utilized when performing a gastro-intestinal (GI) procedure witha gastroscope, a specialized endoscope for GI procedures. FIG. 2 depictsan example embodiment of the cart in greater detail.

With continued reference to FIG. 1, once the cart 11 is properlypositioned, the robotic arms 12 may insert the steerable endoscope 13into the patient robotically, manually, or a combination thereof. Asshown, the steerable endoscope 13 may comprise at least two telescopingparts, such as an inner leader portion and an outer sheath portion, eachportion coupled to a separate instrument driver from the set ofinstrument drivers 28, each instrument driver coupled to the distal endof an individual robotic arm. This linear arrangement of the instrumentdrivers 28, which facilitates coaxially aligning the leader portion withthe sheath portion, creates a “virtual rail” 29 that may be repositionedin space by manipulating the one or more robotic arms 12 into differentangles and/or positions. The virtual rails described herein are depictedin the Figures using dashed lines, and accordingly the dashed lines donot depict any physical structure of the system. Translation of theinstrument drivers 28 along the virtual rail 29 telescopes the innerleader portion relative to the outer sheath portion or advances orretracts the endoscope 13 from the patient. The angle of the virtualrail 29 may be adjusted, translated, and pivoted based on clinicalapplication or physician preference. For example, in bronchoscopy, theangle and position of the virtual rail 29 as shown represents acompromise between providing physician access to the endoscope 13 whileminimizing friction that results from bending the endoscope 13 into thepatient's mouth.

The endoscope 13 may be directed down the patient's trachea and lungsafter insertion using precise commands from the robotic system untilreaching the target destination or operative site. In order to enhancenavigation through the patient's lung network and/or reach the desiredtarget, the endoscope 13 may be manipulated to telescopically extend theinner leader portion from the outer sheath portion to obtain enhancedarticulation and greater bend radius. The use of separate instrumentdrivers 28 also allows the leader portion and sheath portion to bedriven independently of each other.

For example, the endoscope 13 may be directed to deliver a biopsy needleto a target, such as, for example, a lesion or nodule within the lungsof a patient. The needle may be deployed down a working channel thatruns the length of the endoscope to obtain a tissue sample to beanalyzed by a pathologist. Depending on the pathology results,additional tools may be deployed down the working channel of theendoscope for additional biopsies. After identifying a nodule to bemalignant, the endoscope 13 may endoscopically deliver tools to resectthe potentially cancerous tissue. In some instances, diagnostic andtherapeutic treatments may need to be delivered in separate procedures.In those circumstances, the endoscope 13 may also be used to deliver afiducial to “mark” the location of the target nodule as well. In otherinstances, diagnostic and therapeutic treatments may be delivered duringthe same procedure.

The system 10 may also include a movable tower 30, which may beconnected via support cables to the cart 11 to provide support forcontrols, electronics, fluidics, optics, sensors, and/or power to thecart 11. Placing such functionality in the tower 30 allows for a smallerform factor cart 11 that may be more easily adjusted and/orre-positioned by an operating physician and his/her staff. Additionally,the division of functionality between the cart/table and the supporttower 30 reduces operating room clutter and facilitates improvingclinical workflow. While the cart 11 may be positioned close to thepatient, the tower 30 may be stowed in a remote location to stay out ofthe way during a procedure.

In support of the robotic systems described above, the tower 30 mayinclude component(s) of a computer-based control system that storescomputer program instructions, for example, within a non-transitorycomputer-readable storage medium such as a persistent magnetic storagedrive, solid state drive, etc. The execution of those instructions,whether the execution occurs in the tower 30 or the cart 11, may controlthe entire system or sub-system(s) thereof. For example, when executedby a processor of the computer system, the instructions may cause thecomponents of the robotics system to actuate the relevant carriages andarm mounts, actuate the robotics arms, and control the medicalinstruments. For example, in response to receiving the control signal,the motors in the joints of the robotics arms may position the arms intoa certain posture.

The tower 30 may also include a pump, flow meter, valve control, and/orfluid access in order to provide controlled irrigation and aspirationcapabilities to system that may be deployed through the endoscope 13.These components may also be controlled using the computer system of thetower 30. In some embodiments, irrigation and aspiration capabilitiesmay be delivered directly to the endoscope 13 through separate cable(s).

The tower 30 may include a voltage and surge protector designed toprovide filtered and protected electrical power to the cart 11, therebyavoiding placement of a power transformer and other auxiliary powercomponents in the cart 11, resulting in a smaller, more moveable cart11.

The tower 30 may also include support equipment for the sensors deployedthroughout the robotic system 10. For example, the tower 30 may includeoptoelectronics equipment for detecting, receiving, and processing datareceived from the optical sensors or cameras throughout the roboticsystem 10. In combination with the control system, such optoelectronicsequipment may be used to generate real-time images for display in anynumber of consoles deployed throughout the system, including in thetower 30. Similarly, the tower 30 may also include an electronicsubsystem for receiving and processing signals received from deployedelectromagnetic (EM) sensors. The tower 30 may also be used to house andposition an EM field generator for detection by EM sensors in or on themedical instrument.

The tower 30 may also include a console 31 in addition to other consolesavailable in the rest of the system, e.g., console mounted on top of thecart. The console 31 may include a user interface and a display screen,such as a touchscreen, for the physician operator. Consoles in thesystem 10 are generally designed to provide both robotic controls aswell as preoperative and real-time information of the procedure, such asnavigational and localization information of the endoscope 13. When theconsole 31 is not the only console available to the physician, it may beused by a second operator, such as a nurse, to monitor the health orvitals of the patient and the operation of the system 10, as well as toprovide procedure-specific data, such as navigational and localizationinformation. In other embodiments, the console 30 is housed in a bodythat is separate from the tower 30.

The tower 30 may be coupled to the cart 11 and endoscope 13 through oneor more cables or connections (not shown). In some embodiments, thesupport functionality from the tower 30 may be provided through a singlecable to the cart 11, simplifying and de-cluttering the operating room.In other embodiments, specific functionality may be coupled in separatecabling and connections. For example, while power may be providedthrough a single power cable to the cart, the support for controls,optics, fluidics, and/or navigation may be provided through a separatecable.

FIG. 2 provides a detailed illustration of an embodiment of the cartfrom the cart-based robotically-enabled system shown in FIG. 1. The cart11 generally includes an elongated support structure 14 (often referredto as a “column”), a cart base 15, and a console 16 at the top of thecolumn 14. The column 14 may include one or more carriages, such as acarriage 17 (alternatively “arm support”) for supporting the deploymentof one or more robotic arms 12 (three shown in FIG. 2). The carriage 17may include individually configurable arm mounts that rotate along aperpendicular axis to adjust the base of the robotic arms 12 for betterpositioning relative to the patient. The carriage 17 also includes acarriage interface 19 that allows the carriage 17 to verticallytranslate along the column 14.

The carriage interface 19 is connected to the column 14 through slots,such as slot 20, that are positioned on opposite sides of the column 14to guide the vertical translation of the carriage 17. The slot 20contains a vertical translation interface to position and hold thecarriage 17 at various vertical heights relative to the cart base 15.Vertical translation of the carriage 17 allows the cart 11 to adjust thereach of the robotic arms 12 to meet a variety of table heights, patientsizes, and physician preferences. Similarly, the individuallyconfigurable arm mounts on the carriage 17 allow the robotic arm base 21of the robotic arms 12 to be angled in a variety of configurations.

In some embodiments, the slot 20 may be supplemented with slot coversthat are flush and parallel to the slot surface to prevent dirt andfluid ingress into the internal chambers of the column 14 and thevertical translation interface as the carriage 17 vertically translates.The slot covers may be deployed through pairs of spring spoolspositioned near the vertical top and bottom of the slot 20. The coversare coiled within the spools until deployed to extend and retract fromtheir coiled state as the carriage 17 vertically translates up and down.The spring-loading of the spools provides force to retract the coverinto a spool when the carriage 17 translates towards the spool, whilealso maintaining a tight seal when the carriage 17 translates away fromthe spool. The covers may be connected to the carriage 17 using, forexample, brackets in the carriage interface 19 to ensure properextension and retraction of the cover as the carriage 17 translates.

The column 14 may internally comprise mechanisms, such as gears andmotors, that are designed to use a vertically aligned lead screw totranslate the carriage 17 in a mechanized fashion in response to controlsignals generated in response to user inputs, e.g., inputs from theconsole 16.

The robotic arms 12 may generally comprise robotic arm bases 21 and endeffectors 22, separated by a series of linkages 23 that are connected bya series of joints 24, each joint comprising an independent actuator,each actuator comprising an independently controllable motor. Eachindependently controllable joint represents an independent degree offreedom available to the robotic arm 12. Each of the robotic arms 12 mayhave seven joints, and thus provide seven degrees of freedom. Amultitude of joints result in a multitude of degrees of freedom,allowing for “redundant” degrees of freedom. Having redundant degrees offreedom allows the robotic arms 12 to position their respective endeffectors 22 at a specific position, orientation, and trajectory inspace using different linkage positions and joint angles. This allowsfor the system to position and direct a medical instrument from adesired point in space while allowing the physician to move the armjoints into a clinically advantageous position away from the patient tocreate greater access, while avoiding arm collisions.

The cart base 15 balances the weight of the column 14, carriage 17, androbotic arms 12 over the floor. Accordingly, the cart base 15 housesheavier components, such as electronics, motors, power supply, as wellas components that either enable movement and/or immobilize the cart 11.For example, the cart base 15 includes rollable wheel-shaped casters 25that allow for the cart 11 to easily move around the room prior to aprocedure. After reaching the appropriate position, the casters 25 maybe immobilized using wheel locks to hold the cart 11 in place during theprocedure.

Positioned at the vertical end of the column 14, the console 16 allowsfor both a user interface for receiving user input and a display screen(or a dual-purpose device such as, for example, a touchscreen 26) toprovide the physician user with both pre-operative and intra-operativedata. Potential pre-operative data on the touchscreen 26 may includepreoperative plans, navigation and mapping data derived frompreoperative computerized tomography (CT) scans, and/or notes frompreoperative patient interviews. Intraoperative data on display mayinclude optical information provided from the tool, sensor andcoordinate information from sensors, as well as vital patientstatistics, such as respiration, heart rate, and/or pulse. The console16 may be positioned and tilted to allow a physician to access theconsole from the side of the column 14 opposite the carriage 17. Fromthis position, the physician may view the console 16, robotic arms 12,and patient while operating the console 16 from behind the cart 11. Asshown, the console 16 also includes a handle 27 to assist withmaneuvering and stabilizing cart 11.

FIG. 3 illustrates an embodiment of a robotically-enabled system 10arranged for ureteroscopy. In a ureteroscopic procedure, the cart 11 maybe positioned to deliver a ureteroscope 32, a procedure-specificendoscope designed to traverse a patient's urethra and ureter, to thelower abdominal area of the patient. In a ureteroscopy, it may bedesirable for the ureteroscope 32 to be directly aligned with thepatient's urethra to reduce friction and forces on the sensitive anatomyin the area. As shown, the cart 11 may be aligned at the foot of thetable to allow the robotic arms 12 to position the ureteroscope 32 fordirect linear access to the patient's urethra. From the foot of thetable, the robotic arms 12 may insert the ureteroscope 32 along thevirtual rail 33 directly into the patient's lower abdomen through theurethra.

After insertion into the urethra, using similar control techniques as inbronchoscopy, the ureteroscope 32 may be navigated into the bladder,ureters, and/or kidneys for diagnostic and/or therapeutic applications.For example, the ureteroscope 32 may be directed into the ureter andkidneys to break up kidney stone build up using laser or ultrasoniclithotripsy device deployed down the working channel of the ureteroscope32. After lithotripsy is complete, the resulting stone fragments may beremoved using baskets deployed down the ureteroscope 32.

FIG. 4 illustrates an embodiment of a robotically-enabled systemsimilarly arranged for a vascular procedure. In a vascular procedure,the system 10 may be configured such the cart 11 may deliver a medicalinstrument 34, such as a steerable catheter, to an access point in thefemoral artery in the patient's leg. The femoral artery presents both alarger diameter for navigation as well as relatively less circuitous andtortuous path to the patient's heart, which simplifies navigation. As ina ureteroscopic procedure, the cart 11 may be positioned towards thepatient's legs and lower abdomen to allow the robotic arms 12 to providea virtual rail 35 with direct linear access to the femoral artery accesspoint in the patient's thigh/hip region. After insertion into theartery, the medical instrument 34 may be directed and inserted bytranslating the instrument drivers 28. Alternatively, the cart may bepositioned around the patient's upper abdomen in order to reachalternative vascular access points, such as, for example, the carotidand brachial arteries near the shoulder and wrist.

B. Robotic System—Table.

Embodiments of the robotically-enabled medical system may alsoincorporate the patient's table. Incorporation of the table reduces theamount of capital equipment within the operating room by removing thecart, which allows greater access to the patient. FIG. 5 illustrates anembodiment of such a robotically-enabled system arranged for abronchoscopic procedure. System 36 includes a support structure orcolumn 37 for supporting platform 38 (shown as a “table” or “bed”) overthe floor. Much like in the cart-based systems, the end effectors of therobotic arms 39 of the system 36 comprise instrument drivers 42 that aredesigned to manipulate an elongated medical instrument, such as abronchoscope 40 in FIG. 5, through or along a virtual rail 41 formedfrom the linear alignment of the instrument drivers 42. In practice, aC-arm for providing fluoroscopic imaging may be positioned over thepatient's upper abdominal area by placing the emitter and detectoraround the table 38.

FIG. 6 provides an alternative view of the system 36 without the patientand medical instrument for discussion purposes. As shown, the column 37may include one or more carriages 43 shown as ring-shaped in the system36, from which the one or more robotic arms 39 may be based. Thecarriages 43 may translate along a vertical column interface 44 thatruns the length of the column 37 to provide different vantage pointsfrom which the robotic arms 39 may be positioned to reach the patient.The carriage(s) 43 may rotate around the column 37 using a mechanicalmotor positioned within the column 37 to allow the robotic arms 39 tohave access to multiples sides of the table 38, such as, for example,both sides of the patient. In embodiments with multiple carriages, thecarriages may be individually positioned on the column and may translateand/or rotate independently of the other carriages. While carriages 43need not surround the column 37 or even be circular, the ring-shape asshown facilitates rotation of the carriages 43 around the column 37while maintaining structural balance. Rotation and translation of thecarriages 43 allows the system 36 to align the medical instruments, suchas endoscopes and laparoscopes, into different access points on thepatient. In other embodiments (not shown), the system 36 can include apatient table or bed with adjustable arm supports in the form of bars orrails extending alongside it. One or more robotic arms 39 (e.g., via ashoulder with an elbow joint) can be attached to the adjustable armsupports, which can be vertically adjusted. By providing verticaladjustment, the robotic arms 39 are advantageously capable of beingstowed compactly beneath the patient table or bed, and subsequentlyraised during a procedure.

The robotic arms 39 may be mounted on the carriages through a set of armmounts 45 comprising a series of joints that may individually rotateand/or telescopically extend to provide additional configurability tothe robotic arms 39. Additionally, the arm mounts 45 may be positionedon the carriages 43 such that, when the carriages 43 are appropriatelyrotated, the arm mounts 45 may be positioned on either the same side ofthe table 38 (as shown in FIG. 6), on opposite sides of table 38 (asshown in FIG. 9), or on adjacent sides of the table 38 (not shown).

The column 37 structurally provides support for the table 38, and a pathfor vertical translation of the carriages 43. Internally, the column 37may be equipped with lead screws for guiding vertical translation of thecarriages, and motors to mechanize the translation of the carriagesbased the lead screws. The column 37 may also convey power and controlsignals to the carriages 43 and the robotic arms 39 mounted thereon.

The table base 46 serves a similar function as the cart base 15 in cart11 shown in FIG. 2, housing heavier components to balance the table/bed38, the column 37, the carriages 43, and the robotic arms 39. The tablebase 46 may also incorporate rigid casters to provide stability duringprocedures. Deployed from the bottom of the table base 46, the castersmay extend in opposite directions on both sides of the base 46 andretract when the system 36 needs to be moved.

With continued reference to FIG. 6, the system 36 may also include atower (not shown) that divides the functionality of the system 36between the table and the tower to reduce the form factor and bulk ofthe table. As in earlier disclosed embodiments, the tower may provide avariety of support functionalities to table, such as processing,computing, and control capabilities, power, fluidics, and/or optical andsensor processing. The tower may also be movable to be positioned awayfrom the patient to improve physician access and de-clutter theoperating room. Additionally, placing components in the tower allows formore storage space in the table base 46 for potential stowage of therobotic arms 39. The tower may also include a master controller orconsole that provides both a user interface for user input, such askeyboard and/or pendant, as well as a display screen (or touchscreen)for preoperative and intraoperative information, such as real-timeimaging, navigation, and tracking information. In some embodiments, thetower may also contain holders for gas tanks to be used forinsufflation.

In some embodiments, a table base may stow and store the robotic armswhen not in use. FIG. 7 illustrates a system 47 that stows robotic armsin an embodiment of the table-based system. In the system 47, carriages48 may be vertically translated into base 49 to stow robotic arms 50,arm mounts 51, and the carriages 48 within the base 49. Base covers 52may be translated and retracted open to deploy the carriages 48, armmounts 51, and robotic arms 50 around column 53, and closed to stow toprotect them when not in use. The base covers 52 may be sealed with amembrane 54 along the edges of its opening to prevent dirt and fluidingress when closed.

FIG. 8 illustrates an embodiment of a robotically-enabled table-basedsystem configured for a ureteroscopic procedure. In a ureteroscopy, thetable 38 may include a swivel portion 55 for positioning a patientoff-angle from the column 37 and table base 46. The swivel portion 55may rotate or pivot around a pivot point (e.g., located below thepatient's head) in order to position the bottom portion of the swivelportion 55 away from the column 37. For example, the pivoting of theswivel portion 55 allows a C-arm (not shown) to be positioned over thepatient's lower abdomen without competing for space with the column (notshown) below table 38. By rotating the carriage 35 (not shown) aroundthe column 37, the robotic arms 39 may directly insert a ureteroscope 56along a virtual rail 57 into the patient's groin area to reach theurethra. In a ureteroscopy, stirrups 58 may also be fixed to the swivelportion 55 of the table 38 to support the position of the patient's legsduring the procedure and allow clear access to the patient's groin area.

In a laparoscopic procedure, through small incision(s) in the patient'sabdominal wall, minimally invasive instruments may be inserted into thepatient's anatomy. In some embodiments, the minimally invasiveinstruments comprise an elongated rigid member, such as a shaft, whichis used to access anatomy within the patient. After inflation of thepatient's abdominal cavity, the instruments may be directed to performsurgical or medical tasks, such as grasping, cutting, ablating,suturing, etc. In some embodiments, the instruments can comprise ascope, such as a laparoscope. FIG. 9 illustrates an embodiment of arobotically-enabled table-based system configured for a laparoscopicprocedure. As shown in FIG. 9, the carriages 43 of the system 36 may berotated and vertically adjusted to position pairs of the robotic arms 39on opposite sides of the table 38, such that instrument 59 may bepositioned using the arm mounts 45 to be passed through minimalincisions on both sides of the patient to reach his/her abdominalcavity.

To accommodate laparoscopic procedures, the robotically-enabled tablesystem may also tilt the platform to a desired angle. FIG. 10illustrates an embodiment of the robotically-enabled medical system withpitch or tilt adjustment. As shown in FIG. 10, the system 36 mayaccommodate tilt of the table 38 to position one portion of the table ata greater distance from the floor than the other. Additionally, the armmounts 45 may rotate to match the tilt such that the robotic arms 39maintain the same planar relationship with the table 38. To accommodatesteeper angles, the column 37 may also include telescoping portions 60that allow vertical extension of the column 37 to keep the table 38 fromtouching the floor or colliding with the table base 46.

FIG. 11 provides a detailed illustration of the interface between thetable 38 and the column 37. Pitch rotation mechanism 61 may beconfigured to alter the pitch angle of the table 38 relative to thecolumn 37 in multiple degrees of freedom. The pitch rotation mechanism61 may be enabled by the positioning of orthogonal axes 1, 2 at thecolumn-table interface, each axis actuated by a separate motor 3, 4responsive to an electrical pitch angle command. Rotation along onescrew 5 would enable tilt adjustments in one axis 1, while rotationalong the other screw 6 would enable tilt adjustments along the otheraxis 2. In some embodiments, a ball joint can be used to alter the pitchangle of the table 38 relative to the column 37 in multiple degrees offreedom.

For example, pitch adjustments are particularly useful when trying toposition the table in a Trendelenburg position, i.e., position thepatient's lower abdomen at a higher position from the floor than thepatient's upper abdomen, for lower abdominal surgery. The Trendelenburgposition causes the patient's internal organs to slide towards his/herupper abdomen through the force of gravity, clearing out the abdominalcavity for minimally invasive tools to enter and perform lower abdominalsurgical or medical procedures, such as laparoscopic prostatectomy.

C. Instrument Driver & Interface.

The end effectors of the system's robotic arms comprise (i) aninstrument driver (alternatively referred to as “instrument drivemechanism” or “instrument device manipulator”) that incorporateselectro-mechanical means for actuating the medical instrument and (ii) aremovable or detachable medical instrument, which may be devoid of anyelectro-mechanical components, such as motors. This dichotomy may bedriven by the need to sterilize medical instruments used in medicalprocedures, and the inability to adequately sterilize expensive capitalequipment due to their intricate mechanical assemblies and sensitiveelectronics. Accordingly, the medical instruments may be designed to bedetached, removed, and interchanged from the instrument driver (and thusthe system) for individual sterilization or disposal by the physician orthe physician's staff. In contrast, the instrument drivers need not bechanged or sterilized, and may be draped for protection.

FIG. 12 illustrates an example instrument driver. Positioned at thedistal end of a robotic arm, instrument driver 62 comprises of one ormore drive units 63 arranged with parallel axes to provide controlledtorque to a medical instrument via drive shafts 64. Each drive unit 63comprises an individual drive shaft 64 for interacting with theinstrument, a gear head 65 for converting the motor shaft rotation to adesired torque, a motor 66 for generating the drive torque, an encoder67 to measure the speed of the motor shaft and provide feedback to thecontrol circuitry, and control circuitry 68 for receiving controlsignals and actuating the drive unit. Each drive unit 63 beingindependently controlled and motorized, the instrument driver 62 mayprovide multiple (four as shown in FIG. 12) independent drive outputs tothe medical instrument. In operation, the control circuitry 68 wouldreceive a control signal, transmit a motor signal to the motor 66,compare the resulting motor speed as measured by the encoder 67 with thedesired speed, and modulate the motor signal to generate the desiredtorque.

For procedures that require a sterile environment, the robotic systemmay incorporate a drive interface, such as a sterile adapter connectedto a sterile drape, that sits between the instrument driver and themedical instrument. The chief purpose of the sterile adapter is totransfer angular motion from the drive shafts of the instrument driverto the drive inputs of the instrument while maintaining physicalseparation, and thus sterility, between the drive shafts and driveinputs. Accordingly, an example sterile adapter may comprise of a seriesof rotational inputs and outputs intended to be mated with the driveshafts of the instrument driver and drive inputs on the instrument.Connected to the sterile adapter, the sterile drape, comprised of athin, flexible material such as transparent or translucent plastic, isdesigned to cover the capital equipment, such as the instrument driver,robotic arm, and cart (in a cart-based system) or table (in atable-based system). Use of the drape would allow the capital equipmentto be positioned proximate to the patient while still being located inan area not requiring sterilization (i.e., non-sterile field). On theother side of the sterile drape, the medical instrument may interfacewith the patient in an area requiring sterilization (i.e., sterilefield).

D. Medical Instrument.

FIG. 13 illustrates an example medical instrument with a pairedinstrument driver. Like other instruments designed for use with arobotic system, medical instrument 70 comprises an elongated shaft 71(or elongate body) and an instrument base 72. The instrument base 72,also referred to as an “instrument handle” due to its intended designfor manual interaction by the physician, may generally compriserotatable drive inputs 73, e.g., receptacles, pulleys or spools, thatare designed to be mated with drive outputs 74 that extend through adrive interface on instrument driver 75 at the distal end of robotic arm76. When physically connected, latched, and/or coupled, the mated driveinputs 73 of the instrument base 72 may share axes of rotation with thedrive outputs 74 in the instrument driver 75 to allow the transfer oftorque from the drive outputs 74 to the drive inputs 73. In someembodiments, the drive outputs 74 may comprise splines that are designedto mate with receptacles on the drive inputs 73.

The elongated shaft 71 is designed to be delivered through either ananatomical opening or lumen, e.g., as in endoscopy, or a minimallyinvasive incision, e.g., as in laparoscopy. The elongated shaft 71 maybe either flexible (e.g., having properties similar to an endoscope) orrigid (e.g., having properties similar to a laparoscope) or contain acustomized combination of both flexible and rigid portions. Whendesigned for laparoscopy, the distal end of a rigid elongated shaft maybe connected to an end effector extending from a jointed wrist formedfrom a clevis with at least one degree of freedom and a surgical tool ormedical instrument, such as, for example, a grasper or scissors, thatmay be actuated based on force from the tendons as the drive inputsrotate in response to torque received from the drive outputs 74 of theinstrument driver 75. When designed for endoscopy, the distal end of aflexible elongated shaft may include a steerable or controllable bendingsection that may be articulated and bent based on torque received fromthe drive outputs 74 of the instrument driver 75.

Torque from the instrument driver 75 is transmitted down the elongatedshaft 71 using tendons along the elongated shaft 71. These individualtendons, such as pull wires, may be individually anchored to individualdrive inputs 73 within the instrument handle 72. From the handle 72, thetendons are directed down one or more pull lumens along the elongatedshaft 71 and anchored at the distal portion of the elongated shaft 71,or in the wrist at the distal portion of the elongated shaft. During asurgical procedure, such as a laparoscopic, endoscopic or hybridprocedure, these tendons may be coupled to a distally mounted endeffector, such as a wrist, grasper, or scissor. Under such anarrangement, torque exerted on drive inputs 73 would transfer tension tothe tendon, thereby causing the end effector to actuate in some way. Insome embodiments, during a surgical procedure, the tendon may cause ajoint to rotate about an axis, thereby causing the end effector to movein one direction or another. Alternatively, the tendon may be connectedto one or more jaws of a grasper at the distal end of the elongatedshaft 71, where tension from the tendon causes the grasper to close.

In endoscopy, the tendons may be coupled to a bending or articulatingsection positioned along the elongated shaft 71 (e.g., at the distalend) via adhesive, control ring, or other mechanical fixation. Whenfixedly attached to the distal end of a bending section, torque exertedon the drive inputs 73 would be transmitted down the tendons, causingthe softer, bending section (sometimes referred to as the articulablesection or region) to bend or articulate. Along the non-bendingsections, it may be advantageous to spiral or helix the individual pulllumens that direct the individual tendons along (or inside) the walls ofthe endoscope shaft to balance the radial forces that result fromtension in the pull wires. The angle of the spiraling and/or spacingtherebetween may be altered or engineered for specific purposes, whereintighter spiraling exhibits lesser shaft compression under load forces,while lower amounts of spiraling results in greater shaft compressionunder load forces, but limits bending. On the other end of the spectrum,the pull lumens may be directed parallel to the longitudinal axis of theelongated shaft 71 to allow for controlled articulation in the desiredbending or articulable sections.

In endoscopy, the elongated shaft 71 houses a number of components toassist with the robotic procedure. The shaft 71 may comprise of aworking channel for deploying surgical tools (or medical instruments),irrigation, and/or aspiration to the operative region at the distal endof the shaft 71. The shaft 71 may also accommodate wires and/or opticalfibers to transfer signals to/from an optical assembly at the distaltip, which may include an optical camera. The shaft 71 may alsoaccommodate optical fibers to carry light from proximally-located lightsources, such as light emitting diodes, to the distal end of the shaft71.

At the distal end of the instrument 70, the distal tip may also comprisethe opening of a working channel for delivering tools for diagnosticand/or therapy, irrigation, and aspiration to an operative site. Thedistal tip may also include a port for a camera, such as a fiberscope ora digital camera, to capture images of an internal anatomical space.Relatedly, the distal tip may also include ports for light sources forilluminating the anatomical space when using the camera.

In the example of FIG. 13, the drive shaft axes, and thus the driveinput axes, are orthogonal to the axis of the elongated shaft 71. Thisarrangement, however, complicates roll capabilities for the elongatedshaft 71. Rolling the elongated shaft 71 along its axis while keepingthe drive inputs 73 static results in undesirable tangling of thetendons as they extend off the drive inputs 73 and enter pull lumenswithin the elongated shaft 71. The resulting entanglement of suchtendons may disrupt any control algorithms intended to predict movementof the flexible elongated shaft 71 during an endoscopic procedure.

FIG. 14 illustrates an alternative design for an instrument driver andinstrument where the axes of the drive units are parallel to the axis ofthe elongated shaft of the instrument. As shown, a circular instrumentdriver 80 comprises four drive units with their drive outputs 81 alignedin parallel at the end of a robotic arm 82. The drive units, and theirrespective drive outputs 81, are housed in a rotational assembly 83 ofthe instrument driver 80 that is driven by one of the drive units withinthe assembly 83. In response to torque provided by the rotational driveunit, the rotational assembly 83 rotates along a circular bearing thatconnects the rotational assembly 83 to the non-rotational portion 84 ofthe instrument driver. Power and controls signals may be communicatedfrom the non-rotational portion 84 of the instrument driver 80 to therotational assembly 83 through electrical contacts may be maintainedthrough rotation by a brushed slip ring connection (not shown). In otherembodiments, the rotational assembly 83 may be responsive to a separatedrive unit that is integrated into the non-rotatable portion 84, andthus not in parallel to the other drive units. The rotational mechanism83 allows the instrument driver 80 to rotate the drive units, and theirrespective drive outputs 81, as a single unit around an instrumentdriver axis 85.

Like earlier disclosed embodiments, an instrument 86 may comprise anelongated shaft portion 88 and an instrument base 87 (shown with atransparent external skin for discussion purposes) comprising aplurality of drive inputs 89 (such as receptacles, pulleys, and spools)that are configured to receive the drive outputs 81 in the instrumentdriver 80. Unlike prior disclosed embodiments, instrument shaft 88extends from the center of instrument base 87 with an axis substantiallyparallel to the axes of the drive inputs 89, rather than orthogonal asin the design of FIG. 13.

When coupled to the rotational assembly 83 of the instrument driver 80,the medical instrument 86, comprising instrument base 87 and instrumentshaft 88, rotates in combination with the rotational assembly 83 aboutthe instrument driver axis 85. Since the instrument shaft 88 ispositioned at the center of instrument base 87, the instrument shaft 88is coaxial with instrument driver axis 85 when attached. Thus, rotationof the rotational assembly 83 causes the instrument shaft 88 to rotateabout its own longitudinal axis. Moreover, as the instrument base 87rotates with the instrument shaft 88, any tendons connected to the driveinputs 89 in the instrument base 87 are not tangled during rotation.Accordingly, the parallelism of the axes of the drive outputs 81, driveinputs 89, and instrument shaft 88 allows for the shaft rotation withouttangling any control tendons.

E. Navigation and Control.

Traditional endoscopy may involve the use of fluoroscopy (e.g., as maybe delivered through a C-arm) and other forms of radiation-based imagingmodalities to provide endoluminal guidance to an operator physician. Incontrast, the robotic systems contemplated by this disclosure canprovide for non-radiation-based navigational and localization means toreduce physician exposure to radiation and reduce the amount ofequipment within the operating room. As used herein, the term“localization” may refer to determining and/or monitoring the positionof objects in a reference coordinate system. Technologies such aspreoperative mapping, computer vision, real-time EM tracking, and robotcommand data may be used individually or in combination to achieve aradiation-free operating environment. In other cases, whereradiation-based imaging modalities are still used, the preoperativemapping, computer vision, real-time EM tracking, and robot command datamay be used individually or in combination to improve upon theinformation obtained solely through radiation-based imaging modalities.

FIG. 15 is a block diagram illustrating a localization system 90 thatestimates a location of one or more elements of the robotic system, suchas the location of the instrument, in accordance to an exampleembodiment. The localization system 90 may be a set of one or morecomputer devices configured to execute one or more instructions. Thecomputer devices may be embodied by a processor (or processors) andcomputer-readable memory in one or more components discussed above. Byway of example and not limitation, the computer devices may be in thetower 30 shown in FIG. 1, the cart shown in FIGS. 1-4, the beds shown inFIGS. 5-10, etc.

As shown in FIG. 15, the localization system 90 may include alocalization module 95 that processes input data 91-94 to generatelocation data 96 for the distal tip of a medical instrument. Thelocation data 96 may be data or logic that represents a location and/ororientation of the distal end of the instrument relative to a frame ofreference. The frame of reference can be a frame of reference relativeto the anatomy of the patient or to a known object, such as an EM fieldgenerator (see discussion below for the EM field generator).

The various input data 91-94 are now described in greater detail.Pre-operative mapping may be accomplished through the use of thecollection of low dose CT scans. Pre-operative CT scans arereconstructed into three-dimensional images, which are visualized, e.g.as “slices” of a cutaway view of the patient's internal anatomy. Whenanalyzed in the aggregate, image-based models for anatomical cavities,spaces and structures of the patient's anatomy, such as a patient lungnetwork, may be generated. Techniques such as center-line geometry maybe determined and approximated from the CT images to develop athree-dimensional volume of the patient's anatomy, referred to as modeldata 91 (also referred to as “preoperative model data” when generatedusing only preoperative CT scans). The use of center-line geometry isdiscussed in U.S. patent application Ser. No. 14/523,760, the contentsof which are herein incorporated in its entirety. Network topologicalmodels may also be derived from the CT-images, and are particularlyappropriate for bronchoscopy.

In some embodiments, the instrument may be equipped with a camera toprovide vision data (or image) 92. The localization module 95 mayprocess the vision data to enable one or more vision-based (orimage-based) location tracking modules or features. For example, thepreoperative model data may be used in conjunction with the vision data92 to enable computer vision-based tracking of the medical instrument(e.g., an endoscope or an instrument advance through a working channelof the endoscope). For example, using the preoperative model data 91,the robotic system may generate a library of expected endoscopic imagesfrom the model based on the expected path of travel of the endoscope,each image linked to a location within the model. Intraoperatively, thislibrary may be referenced by the robotic system in order to comparereal-time images captured at the camera (e.g., a camera at a distal endof the endoscope) to those in the image library to assist localization.

Other computer vision-based tracking techniques use feature tracking todetermine motion of the camera, and thus the endoscope. Some features ofthe localization module 95 may identify circular geometries in thepreoperative model data 91 that correspond to anatomical lumens andtrack the change of those geometries to determine which anatomical lumenwas selected, as well as the relative rotational and/or translationalmotion of the camera. Use of a topological map may further enhancevision-based algorithms or techniques.

Optical flow, another computer vision-based technique, may analyze thedisplacement and translation of image pixels in a video sequence in thevision data 92 to infer camera movement. Examples of optical flowtechniques may include motion detection, object segmentationcalculations, luminance, motion compensated encoding, stereo disparitymeasurement, etc. Through the comparison of multiple frames overmultiple iterations, movement and location of the camera (and thus theendoscope) may be determined.

The localization module 95 may use real-time EM tracking to generate areal-time location of the endoscope in a global coordinate system thatmay be registered to the patient's anatomy, represented by thepreoperative model. In EM tracking, an EM sensor (or tracker) comprisingof one or more sensor coils embedded in one or more locations andorientations in a medical instrument (e.g., an endoscopic tool) measuresthe variation in the EM field created by one or more static EM fieldgenerators positioned at a known location. The location informationdetected by the EM sensors is stored as EM data 93. The EM fieldgenerator (or transmitter), may be placed close to the patient to createa low intensity magnetic field that the embedded sensor may detect. Themagnetic field induces small currents in the sensor coils of the EMsensor, which may be analyzed to determine the distance and anglebetween the EM sensor and the EM field generator. These distances andorientations may be intra-operatively “registered” to the patientanatomy (e.g., the preoperative model) in order to determine thegeometric transformation that aligns a single location in the coordinatesystem with a position in the pre-operative model of the patient'sanatomy. Once registered, an embedded EM tracker in one or morepositions of the medical instrument (e.g., the distal tip of anendoscope) may provide real-time indications of the progression of themedical instrument through the patient's anatomy.

Robotic command and kinematics data 94 may also be used by thelocalization module 95 to provide localization data 96 for the roboticsystem. Device pitch and yaw resulting from articulation commands may bedetermined during pre-operative calibration. Intra-operatively, thesecalibration measurements may be used in combination with known insertiondepth information to estimate the position of the instrument.Alternatively, these calculations may be analyzed in combination withEM, vision, and/or topological modeling to estimate the position of themedical instrument within the network.

As FIG. 15 shows, a number of other input data can be used by thelocalization module 95. For example, although not shown in FIG. 15, aninstrument utilizing shape-sensing fiber can provide shape data that thelocalization module 95 can use to determine the location and shape ofthe instrument.

The localization module 95 may use the input data 91-94 incombination(s). In some cases, such a combination may use aprobabilistic approach where the localization module 95 assigns aconfidence weight to the location determined from each of the input data91-94. Thus, where the EM data may not be reliable (as may be the casewhere there is EM interference) the confidence of the locationdetermined by the EM data 93 can be decrease and the localization module95 may rely more heavily on the vision data 92 and/or the roboticcommand and kinematics data 94.

As discussed above, the robotic systems discussed herein may be designedto incorporate a combination of one or more of the technologies above.The robotic system's computer-based control system, based in the tower,bed and/or cart, may store computer program instructions, for example,within a non-transitory computer-readable storage medium such as apersistent magnetic storage drive, solid state drive, or the like, that,upon execution, cause the system to receive and analyze sensor data anduser commands, generate control signals throughout the system, anddisplay the navigational and localization data, such as the position ofthe instrument within the global coordinate system, anatomical map, etc.

2. Robotically-Enabled Medical Systems with High Force Instruments

Robotically-enabled medical systems, such as the systems describedabove, can include high force instruments as described in this section.As used herein, a high force instrument can refer to an instrumentincluding an end effector (such as a grasper, gripper, cutter, etc.)that is configured to generate a mechanical advantage whereby inputs areamplified by the structure of the instrument to produce amplifiedoutputs. In some embodiments, force inputs are amplified to produceforce outputs that are greater than the force inputs. For example, insome embodiments, a high force instrument includes an end effectorconfigured as a grasper, and the high force instrument is configuredsuch that input forces (e.g., forces applied on pull wires of theinstrument) are amplified such that output forces at the jaws of thegrasper are greater than the input forces. In some embodiments, the highforce instrument includes a novel structure that provides a mechanicaladvantage that can achieve even greater output than without themechanical advantage. In some embodiments, the high force instrumentsare robotically controlled instruments as described above.

In many of the examples described herein, the end effectors of the highforce instruments are actuated with pull wires. The pull wires may bewrapped around pulleys within the instrument. In some embodiments, thehigh force instruments are capable of outputting a higher force than asimple pulley drive in a wrist configuration. For example, a high forceinstrument may provide a mechanical advantage of two to one, three toone, four to one, five to one, or ten to one. Other mechanicaladvantages are also possible.

In many of the embodiments described below and illustrated in thefigures, the high force instrument is a high force grasper. However, themechanisms described herein that are configured to obtain a high forcecan be applied to other types of instruments as well, including clippingand cutting instruments, among others.

A. Example Instruments with High Force End Effectors

FIG. 16A illustrates a side view of an embodiment of a high forceinstrument 100. As will be discussed below, the instrument 100 can beconfigured to provide a mechanical advantage that can, for example,amplify input forces to produce increased output forces. In theillustrated embodiment, the instrument 100 includes an elongated shaft102 and a handle 104. The elongated shaft 102 extends between a distalend and a proximal end. An end effector 108, which in the illustratedembodiment is configured as a grasper, can be positioned at the distalend of the elongated shaft 102. In some embodiments, for example, asillustrated, the end effector 108 is connected to the distal end of theelongated shaft 102 by a wrist 106. The wrist 106 can be configured toallow one or more degrees of freedom for the instrument 100. Forexample, the wrist 106 can be a two degree-of-freedom wrist. As anexample, a two degree-of-freedom wrist can allow the end effector 108 topivot or rotate around a pitch axis and a yaw axis. In some embodiments,the wrist 106 can be fixed, so as to provide zero degrees of freedom. Insome embodiments, the wrist 106 may allow one, two, three, or moredegrees of freedom. An example embodiment of a wrist 106 and endeffector 108 are shown in greater detail in FIG. 16B, which is describedfurther below.

As shown in FIG. 16A, in some embodiments, the instrument 100 includesthe handle 104. The handle 104 can be configured to connect to aninstrument drive mechanism, for example, as shown in FIGS. 13 and 14,which have been described above. As previously mentioned, the instrument100 may include one or more tendons, cables, or pull wires that extendalong (e.g., through or on) the elongated shaft 102 between the endeffector 108 and the handle 104. The handle 104 may include one or moredrive inputs configured to engage one or more drive outputs on theinstrument drive mechanism (see FIG. 14) that allow the instrument drivemechanism to actuate (e.g., tension or pull) the pull wires. Actuatingthe pull wires can cause motion of the end effector 108 to allow forremote manipulation and control of the end effector 108. For example, insome embodiments, actuation of the pull wires can be configured to causejaws of the end effector 108 to open and close and/or to allow the endeffector 108 to rotate about pitch or yaw axes. As mentioned above, theinstrument drive mechanism can be positioned on a robotic arm. In someembodiments, the robotic arm can be controlled to position, roll,advance, and/or retract the instrument 100.

As shown in FIG. 16A, in some embodiments, the elongated shaft 102extends through the handle 104. In such an embodiment, the elongatedshaft 102 can be configured to advance or retract relative to the handle104. In some embodiments, the instrument drive mechanism is configuredto cause the elongated shaft 102 to advance or retract relative to thehandle 104. This can allow, for example, the handle 104 to remainstationary while the elongated shaft 102 and end effector 108 areadvanced into a patient during a procedure. In some embodiments, theproximal end of the elongated shaft 102 is attached to the handle 104such that the elongated shaft 102 extends only between the end effector108 and the handle 104.

FIG. 16B illustrates a detailed view of the distal end of the instrument100 and shows an embodiment of the wrist 106 and the end effector 108.In the illustrated embodiment, the end effector 108 is configured as agrasper or gripper, although other types of end effectors (e.g., cuttersor snippers) are possible. The end effector 108 includes a first grip orjaw member 118 and a second grip or jaw member 120. The angle betweenthe jaw members 118, 120 can be controlled to operate the end effector108. For example, the jaw members 118, 120 can be opened and closed.

In the illustrated embodiment, the wrist 106 is a two degree-of-freedomwrist, although as mentioned above, the wrist 106 can provide othernumbers of degrees-of-freedom in other embodiments. The illustrated twodegree-of-freedom wrist 106 is configured to allow the end effector 108to pivot around a first axis 110 and a second axis 112. In theillustrated configuration, the second axis 112 extends into and out ofthe plane of the page. The first axis 110 and the second axis 112 can beorthogonal. In some embodiments, the first axis 110 can be a pitch axisand the second axis 112 can be a yaw axis for the instrument 100.

In some embodiments, the instrument 100 includes pulleys 114 and pulleys116. In some embodiments, the pulleys 114 and/or the pulleys 116 can beconsidered part of the instrument 100, part of the wrist 106, and/orpart of the end effector 108. As illustrated, the pulleys 114 areconfigured to rotate around the first axis 110 and the pulleys 116 areconfigured to rotate around the second axis 112. Although notillustrated, pull wires extending along the elongated shaft 102 can bepositioned so as to engage with the pulleys 114 and the pulleys 116. Theend effector 108 can be controlled (e.g., opened, closed, rotated aboutthe first axis 110, and/or rotated about the second axis 112) dependingupon which of the pull wires are actuated.

In some embodiments, the elongated shaft 102, wrist 106, and endeffector 108 can be configured to be inserted into a patient during aminimally invasive procedure, such as a laparoscopic or endoscopicprocedure. For example, in some embodiments, the elongated shaft 102,wrist 106, and end effector 108 are configured to be inserted through asmall incision or other surgical port having a diameter or length ofabout 14 mm or less, about 12 mm or less, or about 10 mm or less. Thus,in some embodiments, a maximum diameter or thickness of the elongatedshaft 102, wrist 106, and end effector 108 can be about or less than 14mm, 12 mm, or 10 mm. Other sizes are also possible. The high forceinstruments described herein can also be used for non-minimally invasiveprocedures, such as open surgery.

Due to the narrowness of the elongated shaft 102, wrist 106, and endeffector 108 (for example, so as to be useable for minimally invasiveprocedures), it can be difficult to provide a structure that configuresthe instrument 100 to provide a mechanical advantage. For example, thesmall diameter or thickness can limit the moment arms through whichforces may be transmitted to distal gripping, clipping and cuttingdevices. With limited moment arms, it can be difficult to get anamplified output and mechanical advantage. However, as will be describedin greater detail below (for example, with reference to FIGS. 17A-20D)the instruments 100 described herein can be configured to advantageouslyprovide a mechanical advantage, while remaining suitable for minimallyinvasive procedures. For example, the instruments 100 can include adistal force amplification mechanism that may allow higher gripping andcutting forces at lower actuation forces while maintaining a smalloverall diameter for the instrument 100.

Various features of the instrument 100 that configure the instrument 100to provide a mechanical advantage will now be described with referenceto FIGS. 17A-20D.

FIGS. 17A and 17B illustrate components of an embodiment of the highforce instrument 100 configured to provide a mechanical advantage. FIG.17A illustrates the instrument 100 in an open position, and FIG. 17Billustrates the instrument 100 in a closed position. In this embodiment,the instrument 100 includes a first jaw member 118, a second jaw member120, a first pulley 122, a second pulley 124 (behind the first pulley122), and a link 126 arranged to provide a mechanical advantage. Thefirst pulley 122 and the second pulley 124 can be the pulleys 116mentioned above.

As illustrated, a proximal end of the first jaw member 118 is connectedto the first pulley 122. The proximal end of the first jaw member 118can be connected to the first pulley 122 by a first drive pin 128. Thefirst drive pin 128 may be integrally formed with the first jaw member118 or the first pulley 122, or may be a separate component (e.g., a rodextending through an opening in both the first jaw member 118 and thefirst pulley 122). Although not visible in FIGS. 17A and 17B, theproximal end of the second jaw member 120 is connected to the secondpulley 124. The proximal end of the second jaw member 120 can beconnected to the second pulley 124 by a second drive pin 130 (notvisible in FIGS. 17A and 17B, but see, for example, FIGS. 24F-24H).Similar to the first drive pin 128, the second drive pin 130 may beintegrally formed with the second jaw member 120 or the second pulley124, or may be a separate component (e.g., a rod extending through anopening in both the second jaw member 120 and the second pulley 124).The first and second drive pins 128, 130 can allow the first and secondjaw members 118, 120 to rotate relative to the first and second pulleys122, 124, respectively.

Opposite the proximal ends, distal ends of the first jaw member 118 andthe second jaw member 120 can each be configured as a component of theend effector 108. For example, the distal ends of the first jaw member118 and the second jaw member 120 can each be configured as a grippingjaw member, a grasping jaw member, a cutting jaw member, a clipping jawmember, etc. In some embodiments, the end effector 108 can comprise acombined end effector that serves multiple functions, such as grippingand cutting. In some embodiments, when the end effector 108 of theinstrument 100 is actuated, distal ends of the first jaw member 118 andthe second jaw member 120 can interact with (e.g., contact) each otherwhen the end effector 108 is closed to provide the end effector function(e.g., gripping or cutting).

The instrument 100 can include the link 126. In some embodiments, thelink 126 can be considered a constraint (e.g., a link constraint or barconstraint). The link 126 can be configured to provide a first pivotpoint (e.g., at first link pin 132) about which the first jaw member 118can pivot and a second pivot point (e.g., at second link pin 134) aboutwhich the second jaw member 120 can pivot to allow the end effector 108to open and close. In some instances, the first and second pivot pointscan be referred to as dual pivots or dual pivot points. In theillustrated embodiment, the link 126 comprises a bar extending betweenthe first jaw member 118 and the second jaw member 120, although inother embodiments, the link 126 may have a different configuration (forexample, in the embodiment shown in FIGS. 25A-25H, the link 126comprises a housing 190 that includes bearing surfaces 192, 194 thatprovide the pivot points).

In the illustrated embodiment, the link 126 is connected on a first endto the first jaw member 118 by a first link pin 132. The first link pin132 may be integrally formed with the first jaw member 118 or the link126, or may be a separate component (e.g., a rod extending through anopening in both the first jaw member 118 and the link 126). The firstlink pin 132 can be configured to allow the first jaw member 126 torotate relative to the link 126. Similarly, the link 126 is connected ona second end to the second jaw member 120 by a second link pin 134. Thesecond link pin 134 may be integrally formed with the second jaw member120 or the link 126, or may be a separate component (e.g., a rodextending through an opening in both the second jaw member 120 and thelink 126). The second link pin 134 can be configured to allow the secondjaw member 126 to rotate relative to the link 126. Thus, in theillustrated embodiment, the link 126 provides a first pivot point at thefirst link pin 132 and a second pivot point at the second link pin 134.

The link 126 can be connected (for example, by the first and second linkpins 132, 134) to the first and second jaw members 118, 120 between theproximal and distal ends of the first and second jaw members 118, 120.As will be discussed below, the position of the link 126, as well as thedistance between the first and second pivot points, can be adjusted tovary the mechanical advantage provided by the instrument 100 (see, forexample, FIGS. 20A-20D, described below).

As shown in FIGS. 17A, and 17B, for some embodiments, the first pulley122 is configured to rotate around a pulley axis 112 (which may be thesecond axis 112 of FIG. 16B). In some embodiments, the pulley axis 112is a central axis. In the illustrated embodiment, the pulley axis 112extends into and out of the plane of the page. Similarly, the secondpulley 124 is configured to rotate around the pulley axis 112. In someembodiments, the axes of the first pulley 122 and the second pulley 124can be substantially aligned. The first pulley 122 and the second pulley124 can be configured such that each can rotate freely. That is,rotation of the first pulley 122 can be independent of rotation of thesecond pulley 124. For example, the first pulley 122 can rotate (e.g.,clockwise or counterclockwise), while the second pulley 124 remainsstationary (or vice versa), or the first pulley 122 can rotate in afirst direction (e.g., either clockwise or counterclockwise), while thesecond pulley 124 rotates in a second direction (e.g. the other ofclockwise or counterclockwise).

The first drive pin 128 can connect to or be positioned on the firstpulley 122 at a radius or distance 136 (illustrated as a dashed line inFIG. 17A) from the pulley axis 112. Although not visible in FIGS. 17Aand 17B, the second drive pin 130 can connect to or be positioned on thesecond pulley 124 at a radius or distance 136 from the pulley axis 112.In some embodiments, the distance 136 for the first pulley 122 can beequal to the distance 136 for the second pulley 124, although this neednot be the case in all embodiments. As will be discussed below, thedistance 136 can be adjusted to vary the mechanical advantage providedby the instrument 100 (see, for example, FIGS. 20A-20D, describedbelow).

One or more pull wires can be engaged with the first pulley 122 that canbe actuated (e.g., pulled) to cause rotation of the first pulley 122 ineither a clockwise or counterclockwise direction around the pulley axis112. Similarly, one or more pull wires can be engaged with the secondpulley 124 that can be actuated (e.g., pulled) to cause rotation of thesecond pulley 124 in either a clockwise or counterclockwise directionaround the pulley axis 112. In some embodiments, the first and secondpulleys 122, 124 are wrapped with pull wires in an a-wrap configuration,as shown for example, in FIG. 21 (described below).

As mentioned above, the pull wires can be pulled or tensioned to actuatethe end effector 108 of the instrument 100. For example, consideringfirst the first pulley 122 and the first jaw member 118, a pull wireengaged with the first pulley 122 can be actuated to cause the firstpulley 122 to rotate about the pulley axis 112. Rotation of the firstpulley 122 is transmitted to the first jaw member 118 through the firstdrive pin 128. For example, considering FIG. 17A, when the first pulley122 is rotated in a clockwise direction, the first drive pin 128 causesthe proximal end of the first jaw member 118 to move to the left (forexample, towards the position shown in FIG. 17B). As the proximal end ofthe first jaw member 118 is moved by rotation of the first pulley 122,the first jaw member 118 pivots about the first pivot point provided bythe link 126, which in the illustrated embodiment, is the first link pin132. Continuing with the example where the first pulley 122 is rotatedin a clockwise direction, this motion of the first jaw member 118 causesthe distal end of the first jaw member 118 to move towards the distalend of the second jaw member (e.g., closing end effector 108 of theinstrument 100, for example, to the position shown in FIG. 17B).Conversely, rotation of the first pulley 122 in the counterclockwisedirection causes the proximal end of the first jaw member 118 to move tothe right, which rotates the first jaw member 118 about the first pivotpoint in the opposite direction, causing the distal end of the first jawmember 118 to move away from the distal end of the second jaw member 120(opening the end effector 108 of the instrument 100).

The second pulley 124 and the second jaw member 120 may provide asimilar motion upon rotation of the second pulley 124. In manyinstances, the second pulley 124 is rotated in the opposite directionthan the first pulley 122, although this need not always be the case.For example, a pull wire engaged with the second pulley 124 can beactuated to cause the second pulley 124 to rotate about the pulley axis112. Rotation of the second pulley 124 is transmitted to the second jawmember 120 through the second drive pin 130. For example, when thesecond pulley 124 is rotated in the counterclockwise direction, thesecond drive pin 130 causes the proximal end of the second jaw member120 to move to the right. As the proximal end of the second jaw member120 is moved by rotation of the second pulley 124, the second jaw member120 pivots about the second pivot point provided by the link 126, whichin the illustrated embodiment, is the second link pin 134. Continuingwith the example where the second pulley 124 is rotated in acounterclockwise direction, this motion of the second jaw member 120causes the distal end of the second jaw member 120 to move towards thedistal end of the first jaw member 118 (e.g., closing end effector 108of the instrument 100, for example, to the position shown in FIG. 17B).Conversely, rotation of the second pulley 124 in the clockwise directioncauses the proximal end of the second jaw member 120 to move to theright, which rotates the second jaw member 120 about the second pivotpoint in the opposite direction, causing the distal end of the secondjaw member 120 to move away from the distal end of the first jaw member118 (opening the end effector 108 of the instrument 100).

The arrangement of the first jaw member 118, the second jaw member 120,the first pulley 122, the second pulley 124, and the link 126 canprovide a mechanical advantage for the instrument 100. For example,considering the first jaw member 118 and the first pulley 122, an inputforce Fin can be applied as shown in FIG. 17A by pulling on a pull wireengaged with the first pulley 122. The arrangement of the first pulley122 and the first jaw member 118 can amplify the force to produce anoutput force Font as illustrated. The output force Font can be amplifiedsuch that the output force Font is greater than the input force Fin.Advantageously, the system herein provides a greater mechanicaladvantage than what can be achieved by a simple pulley-driven grip.

Moment arms L1, L2, L3, and L4 are illustrated in FIG. 17A. Moment armL1 can be equal to the distance between the pulley axis 112 and thepoint where the force Fin is applied from the cable tension. In someembodiments, the moment arm L1 is equal to the radius of the firstpulley 122 or is slightly less than the radius of the first pulley 122.The moment arm L2 can be equal to the distance 136, which as noted aboveis the distance between the pulley axis 112 and the first drive pin 128.In general, the moment arm L2 is less than the moment arm L1. The momentarm L3 is equal to the distance between the first drive pin 128 and thefirst link pin 132. In general, L3 is longer than L2. The moment arm L4is equal to the distance between the first link pin 132 and the distalend of the first jaw member 118. A mechanical advantage can be achievedbecause, when the input force Fin is applied to the pull wire on thefirst pulley 122 at the moment arm L1 to rotate the first pulley 122about the pulley axis 112, this moves the shorter moment arm L2 whichdrives the longer moment arm L3 about the first pivot (e.g., first linkpin 132). Changing moment arm lengths (in particular, increasing momentarm L1 relative to moment arm L2 and/or increasing moment arm L3relative to moment L4) can increase the mechanical advantage.

In some embodiments, to increase grip strength (e.g., output forceFont), the following variables can change in the following directions:increase moment arm L1, decrease moment arm L2, increase moment arm L3,decrease moment arm L4, and/or increase the distance between pivotpoints (e.g., the length of the link 126). In some embodiments, the gripstrength can be increased by changing the aforementioned variables incombination with a secondary geometry change. Those skilled in the artwill appreciate that a wide variety of arrangements for the moment armsL1, L2, L3, and L4 are possible. Further detail about determining themechanical advantage is described below with reference to FIGS. 26A-27.Advantageously, this arrangement (e.g., as described herein) can providea mechanical advantage while maintaining a form factor suitable forminimally invasive surgery as described above.

As shown in the embodiment illustrated in FIGS. 17A and 17B, the firstand second pulleys 122, 124 can be positioned between the proximal endsof the first and second jaw members 118, 120. However, this need not bethe case in all embodiments. For example, FIGS. 18A and 18B illustratean embodiment where the first and second jaw members 118, 120 arepositioned between the first and second pulleys 122, 124. FIG. 18Aillustrates this embodiment of the instrument 100 in the open position,and FIG. 18B illustrates this embodiment of the instrument 100 in theclosed position.

In some embodiments, by placing the first and second pulleys 122, 124 inbetween the first and second jaw members 118, 120 (for example, as shownin FIGS. 17A and 17B), the first and second pulleys 122, 124 can be madewith a larger diameter, which can result in a larger mechanicaladvantage in some instances. This can be at least in part because pulleydiameter can be defined by the chord length of the circle along theplane of the pulley. As you move the pulley closer to the center of acircle, the chord length increases up to the diameter of the circle.

In the embodiments of the instrument 100 shown in FIGS. 17A and 17B andFIGS. 18A and 18B, the link 126 is positioned above first and secondpulleys 122, 124 (relative to the illustrated orientation). This neednot be the case in all embodiments. For example, FIGS. 19A and 19Billustrate an embodiment of the instrument 100 that includes the link126 that is positioned below the first and second pulleys 122, 124. FIG.19A illustrates this embodiment of the instrument 100 in an openposition, and FIG. 19B illustrates this embodiment of the instrument 100in a nearly closed position. Such an arrangement may be advantageous incases where there is more room for mechanisms below the first and secondpulleys 122, 124 rather than above the first and second pulleys 122,124. In some embodiments, the instrument 100 comprises a shaft and awrist having a large enough diameter that provides room to fitcomponents, such as the link 126. Note that an advantage of theembodiment in FIGS. 19A and 19B is that the grips or jaw members 118,120 are capable of opening through a smaller angle for the same opendistance at the tip, thereby resulting in a more parallel closure, whichcan be advantageous for some instruments such as vessel sealers.

In the embodiment of the instrument 100 illustrated in FIGS. 19A and19B, the instrument 100 can include the first jaw member 118, the secondjaw member 120, the first pulley 122, the second pulley 124 (behind thefirst pulley 122), and the link 126 arranged as shown. In thisembodiment, the first jaw member 118 is connected to the first pulley122 by the first drive pin 128 at a position that is positioned betweenthe proximal end of the first jaw member 118 and the distal end of thefirst jaw member 118. The proximal end of the first jaw member 118 isconnected to the link 126 by the first link pin 132 such that the link126 is positioned below the first pulley 122 (e.g., on the side of thefirst pulley 122 opposite the distal end of the first jaw member 118).Similarly, the second jaw member 120 is connected to the second pulley124 by the second drive pin 130 (not visible) at a position that ispositioned between the proximal end of the second jaw member 120 and thedistal end of the second jaw member 120. The proximal end of the secondjaw member 120 is connected to the link 126 by the second link pin 134such that the link 126 is positioned below the second pulley 124 (e.g.,on the side of the second pulley 124 opposite the distal end of thesecond jaw member 120). Like the instruments 100 shown in FIGS. 17A-18B,the instrument 100 of FIGS. 19A and 19B can also provide a mechanicaladvantage.

As noted above, the dimensions of the various components of the highforce instruments 100 can be varied to provide different mechanicaladvantages. Additionally, the starting point for the pivot of L2/L3 maybe adjusted to increase or decrease linear motion of the grips as theyopen and close, as shown in FIGS. 20A-20D. FIGS. 20A and 20B illustratean embodiment the instrument 100 configured for high linear motion andlow back drive, while FIGS. 20C and 20D illustrate an embodiment of theinstrument 100 configured for low linear motion. When the L2/L3 pivotpoint is increased at the end, you get a mechanical leverage due todriving in a circular motion. FIGS. 20A and 20B show this at theextreme, where the two L2/L3 pivot points are directly across thediameter. In this case, any force that tries to back drive the grips isresolved through the radius of the pulley and requires no tension fromthe cables to maintain this point. Similarly, the mechanical leverageincreases to infinity as you approach this point during closure.Accordingly, the dimensions of the components of the instrument 100 canbe designed to provide an optimal trade-off of low linear motion andhigh mechanical advantage.

In some embodiments, first link L1 can be between 3 and 4 mm, the seconddistance of the second link L2 can be between 2 and 3 mm, the thirddistance of the third link L3 can be between 7 and 8 mm, and the fourthdistance of the fourth link L4 can be between 17 and 23 mm. For example,in one embodiment, the first distance of the first link L1 isapproximately 3.35 mm, the second distance of the second link L2 isapproximately 2.5 mm, the third distance of the third link L3 isapproximately 7.3 mm, and the fourth distance of the fourth link L4 isapproximately 20 mm. In some embodiments, a first ratio between thesecond distance of the second link L2 and the first distance of thefirst link L1 is between 0.5 and 1.25, a second ratio between the thirddistance of the third link L3 and the first distance of the first linkL1 is between 1.5 and 3.5, and a third ratio between the fourth distanceof the fourth link L4 and the first distance of the first link L1 isbetween 1.5 and 20. For example, in one embodiment, the first ratiobetween the second distance of the second link L2 and the first distanceof the first link L1 is approximately 0.75, the second ratio between thethird distance of the third link L3 and the first distance of the firstlink L1 is approximately 2.18, and a third ratio between the fourthdistance of the fourth link L4 and the first distance of the first linkL1 is approximately 6. Other sizes for the links L1, L2, L3, and L4, aswell as other ratios between the links are also possible.

FIG. 21 illustrates an example of a pulley (e.g., the first pulley 122or the second pulley 124) engaged with two cable or pull wires 138, 140engaged with the pulley in an a-wrap configuration. In some embodiments,the pull wires 138, 140 are actually cable or pull wire segments 138,140 that are part of a single cable or wire separated by a medial crimp.As illustrated, in the a-wrap configuration, the first pull wire 138extends over a first side of the pulley (e.g., the right side in thefigure), over the top of the pulley, and down a second side of thepulley (e.g., the left side in the figure), before terminating in acrimp pocket 146. Within the crimp pocket 146 the end of the first pullwire 138 is connected or otherwise fixed to the pulley via the medialcrimp. Because the first pull wire 138 wraps nearly all the way aroundthe pulley before terminating at the crimp pocket 146, this providesthat a large amount of rotation can be accomplished by pulling the pullwire 138. For example, the pull wire 138 can cause the pulley to rotatein the clockwise direction from the position illustrated all the wayaround until where the crimp pocket 146 is positioned at the first sideof the pulley. In some embodiments, this can allow, for example, aboutor greater than 270 degrees of rotation.

The second pull wire 140 is similarly wrapped around the pulley, but inthe opposite direction. As illustrated, the second pull wire 140 extendsover the second side of the pulley (e.g., the left side in the figure),over the top of the pulley, and down the first side of the pulley (e.g.,the ride side in the figure), before terminating at the crimp pocket146. Thus, the second pull wire 140 can similarly allow a large rotationof the pulley (e.g., about or greater than 270 degrees) in thecounterclockwise direction.

In some embodiments, the first pull wire 138 and the second pull wire140 are a single pull wire wrapped continuously around the pulley andfixed to the pulley in the crimp pocket 146.

An a-wrap configuration as shown in FIG. 21 can be advantageous in thehigh force instruments 100 described herein because the mechanicaladvantage of these instruments 100 converts larger pulley rotations intohigher forces. Accordingly, the pulley can be configured to allow forlarger rotations, which can in some instances accommodate a larger rangeof motion of the instrument.

FIG. 21 also illustrates that the pulley 122, 124 can include a bore 142configured to receive a pin about which the pulley rotates, and a drivepin bore 144 configured to receive the drive pins 128, 130.

In some embodiments, high force instruments 100 can include one or moreconstraints. As will be described below, the constraints can help toensure that motion of the high force instrument 100 (e.g., opening andclosing the first and second jaw members 118, 120) is consistent andaccurate and/or to stabilize the instrument 100. In certain instances,some embodiments of high force instruments 100 may exhibit unwantedparallelogram motion unless an additional constraint is incorporatedinto the design. For example, in some embodiments, without a constraint,the first and second jaw members 118, 120 can shift relative to eachother (e.g., the first jaw member 118 can shift in an upward directionand the second jaw member 120 can shift in a downward direction) ratherthan opening and closing as desired. In some embodiments, thisundesirable motion is caused by having a multi-link system (e.g., fourlinks) with two pivot points. Inclusion of one or more constraints caneliminate, help prevent, or reduce this undesirable motion, therebystabilizing the high force instrument 100. For example, an additionalconstraint can be incorporated that keeps the first and second jawmembers 118, 120 from sliding relative to each other. Various types ofconstraints are possible and are described in further detail below.

FIGS. 22A-22C illustrate views of an embodiment of the high forceinstrument 100 that includes a constraint formed by a constraint pin 148and a constraint slot 150. FIG. 22A illustrates a front view of thisembodiment of the high force instrument 100, FIG. 22B illustrates a backview of this embodiment of the high force instrument 100, and FIG. 22Cillustrates a side perspective view of this embodiment of the high forceinstrument 100. Note that in FIG. 22A, the pulley 124 and part of theconstraint bar or link 126 are hidden from view. The instrument 100 ofFIGS. 22A-22C includes the first jaw member 118, the second jaw member120, the first pulley 122, the second pulley 124, and the link 126arranged as shown. In the illustrated embodiment, the link 126 ispositioned below the first and second pulleys 122, 124. The first jawmember 118 is connected to the first pulley 122 by the first drive pin128. The second jaw member 120 is connected to the second pulley 124 bythe second drive pin 130. The first and second pulleys 122, 124 rotatearound the pulley axis 112.

As illustrated, the instrument 100 additionally includes a constraintpin 148 and a constraint slot 150. The constraint pin 148 is formed on(or connected to) one of the grip or jaw members (e.g., 120) and extendsthrough a constraint slot 150 formed in the other grip or jaw member(e.g., 118), thereby providing a geared motion between jaw members 118,120. As shown, the first jaw member 118 is connected to the link 126 bythe first link pin 132. The constraint slot 150 can be formed as a curveor cycloid (e.g., formed at a constant radius). In some embodiments, acycloid curve is formed by the path traced by constraint pin 148 in thegrip or jaw member 118 as the jaw members 118, 120 are opened or closedthrough a range of motion, thereby maintaining symmetric angles betweenthe jaw members and midplane. When such a cycloid curve is formed, youadvantageously constrain the motion of the jaw members 118, 120. Inother words, the cycloid curve can match the path of the constraint pin148 when the first and second jaw members 118, 120 are movedsymmetrically to open and close. The constraint pin 148 and constraintslot 150 can keep the first and second jaw members 118, 120 fromshifting in a parallel motion, thereby maintaining a symmetric angleabout the midplane. For example, this can allow the constraint pin 148to move through the constraint slot 150 as the first jaw member 118pivots about the first link pin 132. That is, the constraint slot 150can provide an additional connection between the first jaw member 118and the second jaw member 120, while still allowing the first jaw member118 to pivot relative to the link 126 about the first link pin 132. Insome embodiment, this may help prevent the undesirable shiftingdescribed above and can stabilize the motion of the instrument 100.

While in the present embodiment, the constraint pin 148 extends from thejaw member 120 and into a constraint slot 150 formed in the jaw member118, in other embodiments, the constraint pin 148 extends from the jawmember 118 and into a constraint slot 150 formed in the jaw member 120.

Additionally, for some embodiments, the constraint pin 148 and theconstraint slot 150 can constrain motion of the first jaw member 118 tomotion of the second jaw member 120. That is, these constraints cancause motion of the first jaw member 118 to cause a corresponding motionof the second jaw member 120 (or vice versa). For example, if the firstjaw member 118 opens five degrees, these constraints cause the secondjaw member 120 to open five degrees. In some embodiments, thecorresponding motion of the second jaw member 120 is imperfect such thatit will not correspond exactly to motion of the first jaw member 118(e.g., if the first jaw member 118 opens five degrees, these constraintscan cause the second jaw member 120 to open 5.5 degrees).

In some embodiments, these constraints (e.g., the constraint pin 148 andthe constraint slot 150) can be considered a pin based cycloidconstraint. In some embodiments, these constraints can be considered ageared restraint because they gear motion of the first jaw member 118 tomotion of the second jaw member 120.

FIG. 22A also illustrates that, in some embodiments, the instrument 100can include a pulley axle clearance slot 152. The pulley axle clearanceslot 152 can help to provide clearance for the motion of the first jawmember 118 over the pulley drive pin, so that the first jaw member 118will open and not be limited in its range of motion. Although notvisible, the second jaw member 120 can also include a similar pulleyaxle clearance slot.

FIG. 23 illustrates a front view of another embodiment of the high forceinstrument 100 that includes the constraint pin 148 and the constraintslot 150 (similar to those described above), and which is furtherconfigured such that the drive pins 128, 130 are positioned so that theynever move to a position where they overlap. In some embodiments, it hasbeen observed that if the drive pins 128, 130 move to a position inwhich they overlap, the first and second jaw members 118, 120 can rotateor pivot together around the aligned drive pins 128, 130. Keeping thedrive pins 128, 130 apart, either in a radial distance, an angulardistance, or both, may help to prevent this motion.

The instrument 100 of FIG. 23 includes the first jaw member 118, thesecond jaw member 120, the first pulley 122, the second pulley 124, andthe link 126 arranged as shown. In the illustrated embodiment, the link126 is positioned above the first and second pulleys 122, 124. The firstjaw member 118 is connected to the first pulley 122 by the first drivepin 128, and the second jaw member 120 is connected to the second pulley124 by the second drive pin 130. The first and second pulleys 122, 124rotate around the pulley axis 112 as described above. Additionally, theinstrument 100 includes the constraint pin 148 and the constraint slot150 as described above. Although in this embodiment, the link 126 ispositioned above the pulleys 122, 124.

In addition, in this embodiment, each of the drive pins 128, 130 arepositioned so that they never move to an overlapping position. Forexample, the instrument 100 is illustrated in a closed position (withthe first jaw member 118 contacting the second jaw member 120), and inthis position, the drive pins 128, 130 are positioned as shown. Becausethe first jaw member 118 contacts the second jaw member 120, the firstdrive pin 128 is prevented from further rotation in the clockwisedirection and the second drive pin 130 is prevented from furtherrotation in the counterclockwise direction. From this position, thefirst and second drive pins 128, 130 can only rotate in the directionsindicated with arrows in the figure. That is, as the instrument 100opens, the first drive pin 128 can only rotate in the counterclockwisedirection and the second drive pin 130 can only rotate in the clockwisedirection. As such, the first and second drive pins 128, 130 arepositioned so as to not overlap during any portion of the motion, whichcan improve the stability of the instrument 100.

In some embodiments, by keeping the drive pins 128, 130 apart (e.g.,preventing overlapping), the range of motion of the first and second jawmembers 118, 120 can be limited. This is because preventing the drivepins 128, 130 from overlapping reduces the total amount of rotationavailable for each of the first and second pulleys 122, 124. This canreduce the total amount of work (and thus force) that can be transferredfrom the input to the output. Thus, some embodiments that includenon-overlapping drive pins 128, 130 (like the instrument 100 of FIG. 23)trade jaw motion or force amplification for stability. Those of skill inthe art will, upon consideration of this disclosure, appreciate thatthis trade off can be selected so at to maximize performance of theinstrument 100 for a given situation.

In some embodiments, even with a pin based cycloid constraint (such asthe constraint formed by the constraint pin 148 and the constraint slot150 in FIGS. 22A and 23), the instrument 100 may still exhibitundesirable instability due to manufacturing tolerance stack up. In someembodiments, this instability can be eliminated or reduced, by replacingthe pin based cycloid constraint with a tooth based cycloid constraint.Like a pin based cycloid constraint, a tooth based cycloid constraintcan be considered a type of geared constraint. With a tooth basedcycloid constraint, one jaw member is formed with a tooth that extendsinto a notch of the other jaw member, thereby helping to preventundesirable shifting of the jaw members during use. The embodiments ofthe instrument 100 shown in FIGS. 24A-24H and FIGS. 25A-25H describedbelow, include examples of a tooth based cycloid constraint.

In some embodiments, to address the drawbacks associated with preventingthe drive pins 128, 130 from overlapping, rather than limiting theability of the drive pins 128, 130 to overlap and cross, the instrument100 can include a slot constraint. The slot constraint can prevent orreduce instability in the instrument 100 even while the drive pins 128,130 overlap. As will be described in greater detail below, the slotconstraint can be formed as a trough or slot between two ears. As thedrive pins 128, 130 overlap into alignment and cross over, the ears ofthe slot constraint can abut and contact the central pin of the pulleys122, 124, thereby preventing undesirable rotation of the first andsecond jaw members 118, 120. As the drive pins are capable of crossing,these designs may include a unique feature in that they are capable ofgetting more force advantage than designs that limit or prevent crossingof the drive pins 128, 130. In addition, these designs can provide aunique force profile in which the gripping force is highest when thegrips are closed (see FIG. 27 below and the corresponding description).FIGS. 24A-24H illustrate an embodiment that includes a slot constraint.

FIGS. 24A-24H illustrate views of an embodiment of the high forceinstrument 100 that includes a geared constraint (configured as a toothbased cycloid constraint) and a slot constraint. FIG. 24A is a frontview of the instrument 100 in an open position, FIG. 24B is an explodedview of the instrument 100, FIG. 24C is a side view of the instrument100, FIG. 24D is a back view of the instrument 100 in an open position,and FIG. 24E is a bottom cross-sectional view of the instrument 100through the center pin. FIGS. 24F-24H illustrate the drive pins 128, 130crossing as the instrument 100 moves from an open position to a closedposition.

As best shown in the exploded view of FIG. 24B, the instrument 100includes the first jaw member 118, which can be configured as shown. Forexample, the first jaw member 118 can include the first drive pin 128positioned at the proximal end of the first jaw member 118.Alternatively, the first drive pin 128 may be formed as part of thefirst pulley 122 or as a separate piece as mentioned above. The firstjaw member 118 may also include a hole or opening 166, which providesline of site access to the junction of first link pin 132 and opening162 (discussed below), so that the assembly can be laser welded togetherif desired. An additional hole, opening, recess or divot (not shown) canbe formed on an inner surface of the first jaw member 118 to engage thepin 132. The first jaw member 118 may also include a notch 171 formed byan upper surface 172 and a lower surface 170. As will be describedbelow, the upper and lower surfaces 172, 170 that form the first notchwill engage with corresponding features on the second jaw member 120 toform a geared constraint or tooth based cycloid constraint (see FIG.24A, for example). The first jaw member 118 may also include a slot 186.The slot 186 may be configured to receive an end of a first piece 153 ofthe link 126.

The second jaw member 120 can include the second drive pin 130positioned at the proximal end of the second jaw member 120.Alternatively, the second drive pin 130 may be formed as part of thesecond pulley 124 or as a separate piece as mentioned above. The secondjaw member 120 may also include an opening 168 configured to receive thesecond link pin 134. The second jaw member 120 may also include a tooth175 having an upper surface 174 and a lower surface 176. As will bedescribed below, the upper and lower surfaces 174, 176 of the tooth 174will engage with corresponding features on the first jaw member 118 toform the geared constraint or tooth based cycloid constraint (see FIG.24A, for example). The second jaw member 120 may also include a slot188. The slot 188 may be configured to receive an end of a second piece154 of the link 126. In some embodiments, the tooth 175 comprises anextension or protrusion that can appear as a triangular fin. In otherembodiments, the tooth 175 comprises an extension or protrusion inanother shape, such as peg-shaped. The recess or notch 171 that receivesthe tooth 175 is large enough to provide clearance for the tooth 175 asthe jaw members 118, 120 open and close. In some embodiments, a cycloidconstraint is formed such that the lower surface 170 of the notch 171 ismaintained in contact with the lower surface 174 of the tooth 175, whilethe upper surface of the notch 172 is maintained in contact with theupper surface 176 of the tooth 175 during the opening and closing of thejaw members.

The first pulley 122 may include a pulley axis opening 178. The pulleyaxis opening is configured to be mounted on a pulley pin 160. The pulleypin 160 may be aligned with the pulley axis 112 (described above). Thefirst pulley 122 rotates about the pulley pin 160. The first pulley 122may also include a hole 180 for receiving the first drive pin 128.Similarly, the second pulley 124 may include a pulley axis opening 182configured to be mounted on the pulley pin 160 to allow the secondpulley 124 to rotate about the pulley pin 160. The second pulley 124 mayalso include a hole 184 for receiving the second drive pin 130.

In the embodiment of FIGS. 24A-24H, the link 126 is formed by a firstpiece 153 and a second piece 154. The first piece 153 includes anopening 162 for receiving the first link pin 132 therethrough. Theportion of the first piece 153 that includes the opening 162 may beconfigured so as to be received in the slot 186 of the first jaw member118, such that the first link pin 132 can extend through the opening 162in the first piece and into or through the opening 166 in the first jawmember 118. As shown in FIG. 24B, the first piece 153 of the link 126may also include the second link pin 134. In some embodiments, thesecond link pin 134 is integrally formed with the first piece 153. Inother embodiments, the second link pin 134 can be a separate piece orintegrally formed with the second jaw member 120. The first piece 153 ofthe link 126 also includes an ear 156 as shown. The ear 156 can beformed as a downward projection or protrusion. As will be discussedbelow, an inner surface of the ear 156 can contact the pulley pin 160when assembled to prevent or reduce instability in the instrument 100when the drive pins 128, 130 are aligned.

As mentioned above, the link 126 can be formed by the first piece 153and the second piece 154. The second piece 154 can include an opening164 for receiving the second link pin 134 therethrough. The portion ofthe second piece 154 that includes the opening 164 may be configured soas to be received in the slot 188 of the second jaw member 120, suchthat the second link pin 134 can extend through the opening 164 in thesecond piece 154 and into or through the opening 168 in the second jawmember 120. As shown in FIG. 24B, the second piece 154 of the link 126may also include the first link pin 132. In some embodiments, the firstlink pin 132 is integrally formed with the second piece 154. In otherembodiments, the first link pin 132 can be a separate piece orintegrally formed with the first jaw member 118. The second piece 154 ofthe link 126 also includes an ear 158 as shown. The ear 158 can beformed as a downward projection or protrusion. As will be discussedbelow, an inner surface of the ear 158 can contact the pulley pin 160when assembled to prevent or reduce instability in the instrument 100when the drive pins 128, 130 are aligned.

As shown for example in FIG. 24A, when assembled, the tooth 175 of thesecond jaw member 120 is received in the groove or notch 171 of thefirst jaw member 118. This interaction between the first and second jawmembers 118, 120 provides a geared restraint or a tooth based cycloidrestraint for the instrument 100. This constraint can constrain motionof the first jaw member 118 to the second jaw 120 similar to the pinbased cycloid restraint described above with reference to FIGS. 22A and23. This constraint can also improve the stability of the instrument 100by, for example, preventing or reducing parallel motion between thefirst and second jaw members 118, 120. In some embodiments, an advantageof this constraint is that it may be less susceptible to manufacturingtolerance errors than other types of restraints, such as the pin basedcycloid constraint. In other embodiments, more than one tooth (e.g.,first and second teeth) can be provided between the first and second jawmembers to provide a tooth-based geared constraint.

Additionally, when assembled, the instrument 100 can include a slotconstraint that is configured to prevent instability when the drive pins128, 130 are aligned. This can mean that the embodiment of FIGS. 24A-24Hcan advantageously be used in designs that allow the drive pins 128, 130to overlap or cross. By having the drive pins 128, 130 overlap or cross,more work can be performed by the pulleys, thereby resulting in adesirable greater force output. As shown in FIGS. 24A, 24D, and 24E, thepulley pin 160 is received between the first jaw member 118 and the ear156 of the first piece 153 of the link 126. Similarly, the pulley pin160 is also received between the second jaw member 120 and the ear 158of the second piece 154 of the link 126. In some embodiments, the ears156, 158 of the first and second pieces 153, 154 of the link 126 form aslot or channel. The pulley pin 160 rides within and contacts thischannel during motion of the instrument 100. This contact provides anadded point of stability, which can stabilize the instrument 100 whilethe drive pins 128, 130 overlap.

FIGS. 24F-24H illustrate the function of the slot restraint (formed bythe ears 156, 158 and the pulley pin 160) to stabilize the instrument100 while the drive pins 128, 130 overlap and cross during motion of theinstrument 100. FIGS. 24F-24H illustrate various stages during a closingmotion of the instrument 100. As shown in FIG. 24F, the first and secondjaw members 118, 120 are in an open position and the first drive pin 128is located to the right (relative to the orientation shown in thefigure) of the second drive pin 130. The instrument 100 is in arelatively stable position because the drive pins 128, 130 are spacedapart. This position is further stabilized by the additional contact ofthe pulley pin 160 with the slot formed between the ears 156, 158.

As the instrument 100 closes further, to the position illustrated inFIG. 24G, the drive pins 128, 130 begin to overlap and cross.Specifically, the first drive pin 128 has rotated clockwise from theposition in FIG. 24F to the position shown in FIG. 24G, and the seconddrive pin 130 has rotated counterclockwise from the position in FIG. 24Fto the position shown in FIG. 24G. In this position (FIG. 24G), with thedrive pins 128, 130 overlapping as shown, the instrument 100 would be ina relatively unstable position absent the slot constraint formed by thepulley pin 160 and the ears 158, 156. That is, absent the slotconstraint, the instrument 100 may tend to rotate about the axis of thealigned drive pins 128, 130. The slot constraint, however,advantageously stabilizes the instrument 100 against this motion. Forexample, contact between the pulley pin 160 and the ear 156 prevents theinstrument from rotating in a clockwise direction and contact betweenthe pulley pin 160 and the ear 158 prevents the instrument from rotatingin a counterclockwise direction.

As shown in FIG. 24H, as the instrument 100 closes further, the drivepins 128, 130 rotate pass each other. For example, the first drive pin128 is now positioned to the left of the second drive pin 130. Again,this position is relatively stable because the drive pins 128, 130 areseparated and the slot constraint provides additional stability.

Considering the position of the pulley pin 160 with the slot formedbetween the ears 156, 158 in FIGS. 24F-24H, it can be seen that, in someembodiments, the pulley pin 160 moves along the slot during motion ofthe instrument 100.

The embodiment of the instrument 100 shown in FIGS. 24A-24H expands uponthe force amplification and constraint concepts described above withreference to the previous embodiments by including both the gearedrestraint (e.g., the tooth based cycloid constraint) and the slotconstraint. In some circumstances, both the constraints may have limitsto their pulley range of motion, but, advantageously, such limits canoccur at different angles. The two constraints can be implementedtogether, and thus it is possible to have an instrument that includesboth constraints (as shown in FIGS. 24A-24H). By using both constraints,it is possible to extend the range of motion of the pulleys 122, 124 tobe almost double that of an embodiment that limits crossing of the drivepins. This in turn increases the amount of force that can be deliveredfor a given range of motion. Having both constraints can reduce theinstability to be approximately the minimum of either constraint ateither angle.

FIGS. 25A-25H illustrate an embodiment of the instrument 100 thatincludes two constraints as described above, but that reduces theoverall number of components in the instrument 100. Such an embodimentmay advantageously simplify manufacture and assembly of the instrument100. FIGS. 25A and 25B illustrate views of the instrument 100 in an openand closed configuration, respectively. FIG. 25C illustrates anembodiment of a housing 190 that serves as the link 126 for theinstrument 100. FIG. 25D illustrates a view of the first or second jawmember 118, 120. FIGS. 25E-25H illustrate stages during an exampleassembly process for the instrument 100.

As shown in FIGS. 25A and 25B, and shown alone in FIG. 25C, theinstrument 100 includes a link 126 that is formed as a single housing190. As best seen in FIG. 25C, the housing 190 can include a firstbearing surface 192 and a second bearing surface 194. Each of the firstand second bearing surfaces 192, 194 can be formed as a rod or cylinderextending across the housing 190. As will be described below, thebearing surfaces 192, 194 provide the pivot points on which the firstand second jaw members 118, 120 can pivot. In some respects, the firstand second bearing surfaces replace the first and second link pins 132,134 in the previously described embodiments.

The housing 190 can also include a slot 195 as shown. The slot 195 canbe configured to engage the pulley pin 160 to form the slot constraintdescribed above. The slot constraint can provide stability for theinstrument 100 when the drive pins 128, 130 are aligned.

In some embodiments, the housing 190 advantageously provides the samefunctionality as the first and second pieces 153, 154 of the link 126 ofthe embodiment of FIGS. 24A-24H in only a single piece. This mayadvantageously reduce the complexity of the design.

FIG. 25D illustrates an embodiment a jaw member (either the first jawmember 118 or the second jaw member 120). In FIG. 25D, the describedfeatures have been numbered twice to describe both the first jaw member118 and the second jaw member 120. As illustrated, the jaw member 118,120 includes a tooth 175 configured to engage a corresponding recess 171on the opposite jaw member. The interactions between the teeth 175 andthe recesses 171 provide a geared restraint (or a tooth based cycloidconstraint) as described above.

The jaw members 118, 120 also include a groove 196, 198. The grooves196, 198 are configured to receive the bearing surfaces 192, 194 of thehousing 190. For example, when assembled (FIGS. 25A and 25B) the groove196 of the first jaw member 118 receives the first bearing surface 192to allow the first jaw member 118 to pivot about the first bearingsurface 192. Similarly, the groove 198 of the second jaw member 120receives the second bearing surface 194 to allow the second jaw member120 to pivot about the second bearing surface 194.

As shown in FIGS. 25A and 25B, the teeth 175 and the recesses 171provide the geared restraint (or a tooth based cycloid constraint) andthe slot 195 and pulley pin 160 provide the slot restraint. Accordingly,the embodiment of the instrument 100 of FIGS. 25A-25H can provide thesame advantages as the embodiment of the instrument 100 of FIGS. 24A-24Hdescribed above. Additionally, the total number of parts of theembodiment of the instrument 100 of FIGS. 25A-25H is reduced.

FIGS. 25E-25F illustrate an example assembly process for the instrument100.

As shown, the first and second jaw members 118, 120 can be positionedabove the housing 190 (FIG. 24E). The first and second jaw members 118,120 can be dropped into the housing 190 and rotated as shown in FIG.25F. As shown in FIG. 25G, the first and second jaw members 118, 120 canthen drop further down so that the grooves 196, 198 formed in the backof the first and second jaw members 118, 120 are concentric with thebearing surfaces 192, 194 of the housing. From this position, the firstand second jaw members 118, 120 are further rotated to the position ofFIG. 25H so that they are held in place by the housing 190. Although notillustrated, assembly can further include additional steps such asattaching the pulleys 122, 124 and attaching to a wrist 106, amongothers.

Returning to FIGS. 25A and 25B, in some embodiments, the first jawmember 118 is constrained by the second jaw member 120 and the bearingsurfaces 192, 194 of the housing 190 during the entire range of motion.Once the assembly is installed in the distal clevis of the wrist 106,the range of motion can be limited to the working range of motion, whichcan be smaller than the angle required for disassembly.

The instrument 100 illustrated in FIGS. 25A-25B has the benefit of fewerparts and the potential to be made smaller than other embodiments. Insome instances, another advantage of the present embodiment is that theslot 195 can provide more stability through tolerance issues as the slot195 engages with either side of the pin 160 at each side of the jaws,which prevents the wrist from having torsional slop. Generally, otherassembly methods require either additional parts or additional machiningoperations to ensure that the grips are held in their correct pivotsfollowed by a swaging or laser welding process to join them together.This instrument 100 constrains the jaw members in the correct positionin the range of motion used by the mechanism, but allows the parts to beassembled when the jaw members are over rotated. This has benefits insurgical instrument tip because as the link 126 is a single piecehousing 190, it can be made smaller than other embodiments. Accordingly,in some embodiments, the link 126 can be stronger and have highertolerances because it is a single structure. The reduced part count andreduced assembly time may reduce the cost. Some of these benefits canstill be realized even if the link 126 is made out of multiple pieces.

The teeth in any of the embodiments describe above do not need to becycloid. In some embodiments, the teeth could comprise some otherprofile, including involutes.

B. Determining the Mechanical Advantage/Amplification of a High ForceInstrument

This section discusses how one can determine the mechanical advantage ofthe high force instruments 100 described above. At a high level, theamplification ratio is the ratio between the input range of motion andthe output range of motion. For the instruments 100 described above, theinput range of motion can be related to the geometry and dimensions ofthe pulleys and the output range of motion can be related to thegeometry and dimension of the jaw members.

When determining the mechanical advantage and amplification of theserobotically controlled high force instruments 100, one metric toconsider is effective pulley diameter. A high force instrument 100 canbe abstracted as a mechanism that creates an output torque on a pair ofjaw members from a tension applied via a pull wire or cable. Thesimplest way to create an output torque on the pair of jaw members is toattach the jaw members directly and rigidly to the pulley. Thisarchitecture is limited, however, in how much torque it can provide bythe diameter of the pulley that can fit in the diameter of theshaft/tube through which it passes. Therefore, it is desirable to have amechanism that can provide a mechanical advantage over a simple pulley.

The mechanical advantage can be determined by calculating the pulleydiameter that would have to be used to yield an equivalent gripping(output) torque. This is referred to as the effective diameter d_(eff)and can be determined by Equation 1:

$\begin{matrix}{d_{eff} = {\tau_{grip}*\frac{2}{F}}} & \left( {{Eq}.\mspace{14mu} 1} \right)\end{matrix}$

wherein d_(eff) is the effective diameter, τ_(grtp) is the gripping(output) torque, and F is the input torque. With reference to FIG. 26A,gripping torque is related to the geometry of the jaw member by Equation2:

τ_(grtp) =F _(grtp) *h ₂  (Eq. 2)

Thus, the effective diameter can be determined by Equation 3:

$\begin{matrix}{d_{eff} = {F_{grip}*h_{2}*\frac{2}{F_{cable}}}} & \left( {{Eq}.\mspace{14mu} 3} \right)\end{matrix}$

wherein F_(cable) is the tensile force that acts on a cable of thepulley as shown in FIG. 26B.

FIG. 27 illustrates a representative force profile for one embodiment ofa high force instrument 100 that is capable of having crossing drivepins (for example, similar to the embodiments of FIGS. 24A-24H and FIGS.25A-25H). The illustrated force profile is for an instrument 100 havingan 8 mm wrist and 6.7 mm drive pulleys.

The force profile shows the effective pulley diameter of the instrument100 as a function of grip open angle. As illustrated, when the grips(jaw members) are nearly closed (0 degree open angle), the effectivepulley diameter is around 26 mm. Since the diameter of the drive pulleyis 6.7 mm, we are able to achieve a mechanical advantage of 3.88 times(26 mm/6.7 mm) the force that could be achieved with a simple lever andpulley system As the grip angle increases (e.g., to 40 degrees), theeffective pulley diameter decreases, such that at 40 degrees, themechanical advantage is about 3.28 times (22 mm/6.7 mm) the force thatcould be achieved with a simple lever and pulley system. Accordingly, weare able to achieve a mechanical advantage that is at least 3 times orgreater than the force that could be achieved with a simple pulley andlever system. Furthermore, the force profile shows that our the dualdrive pin design is unique in that it allows the drive pins to crosssuch that the grips can grip hardest at the close angle (grip open angleof zero degrees).

3. Implementing Systems and Terminology

Implementations disclosed herein provide systems, methods and apparatusfor robotically-enabled medical systems. Various implementationsdescribed herein include robotically-enabled medical systems with highforce instruments.

It should be noted that the terms “couple,” “coupling,” “coupled” orother variations of the word couple as used herein may indicate eitheran indirect connection or a direct connection. For example, if a firstcomponent is “coupled” to a second component, the first component may beeither indirectly connected to the second component via anothercomponent or directly connected to the second component.

The position estimation and robotic motion actuation functions describedherein may be stored as one or more instructions on a processor-readableor computer-readable medium. The term “computer-readable medium” refersto any available medium that can be accessed by a computer or processor.By way of example, and not limitation, such a medium may comprise randomaccess memory (RAM), read-only memory (ROM), electrically erasableprogrammable read-only memory (EEPROM), flash memory, compact discread-only memory (CD-ROM) or other optical disk storage, magnetic diskstorage or other magnetic storage devices, or any other medium that canbe used to store desired program code in the form of instructions ordata structures and that can be accessed by a computer. It should benoted that a computer-readable medium may be tangible andnon-transitory. As used herein, the term “code” may refer to software,instructions, code or data that is/are executable by a computing deviceor processor.

The methods disclosed herein comprise one or more steps or actions forachieving the described method. The method steps and/or actions may beinterchanged with one another without departing from the scope of theclaims. In other words, unless a specific order of steps or actions isrequired for proper operation of the method that is being described, theorder and/or use of specific steps and/or actions may be modifiedwithout departing from the scope of the claims.

As used herein, the term “plurality” denotes two or more. For example, aplurality of components indicates two or more components. The term“determining” encompasses a wide variety of actions and, therefore,“determining” can include calculating, computing, processing, deriving,investigating, looking up (e.g., looking up in a table, a database oranother data structure), ascertaining and the like. Also, “determining”can include receiving (e.g., receiving information), accessing (e.g.,accessing data in a memory) and the like. Also, “determining” caninclude resolving, selecting, choosing, establishing and the like.

The phrase “based on” does not mean “based only on,” unless expresslyspecified otherwise. In other words, the phrase “based on” describesboth “based only on” and “based at least on.”

As used herein, the term “approximately” or “about” refers to a range ofmeasurements of a length, thickness, a quantity, time period, or othermeasurable value. Such range of measurements encompasses variations of+/−10% or less, preferably +/−5% or less, more preferably +/−1% or less,and still more preferably +/−0.1% or less, of and from the specifiedvalue, in so far as such variations are appropriate in order to functionin the disclosed devices, systems, and techniques.

The previous description of the disclosed implementations is provided toenable any person skilled in the art to make or use the presentinvention. Various modifications to these implementations will bereadily apparent to those skilled in the art, and the generic principlesdefined herein may be applied to other implementations without departingfrom the scope of the invention. For example, it will be appreciatedthat one of ordinary skill in the art will be able to employ a numbercorresponding alternative and equivalent structural details, such asequivalent ways of fastening, mounting, coupling, or engaging toolcomponents, equivalent mechanisms for producing particular actuationmotions, and equivalent mechanisms for delivering electrical energy.Thus, the present invention is not intended to be limited to theimplementations shown herein but is to be accorded the widest scopeconsistent with the principles and novel features disclosed herein.

1. A robotic system comprising: an instrument having an end effector,the instrument comprising: a first pulley configured to rotate about apulley axis; a first jaw member connected to the first pulley by a firstdrive pin; a second pulley configured to rotate about the pulley axis; asecond jaw member connected to the second pulley by a second drive pin;and a link providing a first pivot point about which the first jawmember can pivot and a second pivot point about which the second jawmember can pivot.
 2. The robotic system of claim 1, further comprising arobotic arm coupled to the instrument.
 3. The robotic system of claim 1,wherein: rotation of the first pulley causes rotation of the first drivepin about the pulley axis, further causing the first jaw member to pivotabout the first pivot point; and rotation of the second pulley causesrotation of the second drive pin about the pulley axis, further causingthe second jaw member to pivot about the second pivot point.
 4. Therobotic system of claim 1, further comprising a geared constraintconfigured to constrain motion of the first jaw member and the secondjaw member such that motion of one of the first jaw member and thesecond jaw member causes a substantially corresponding motion of theother of the first jaw member and the second jaw member.
 5. The roboticsystem of claim 4, wherein the geared constraint comprises a cycloidconstraint, the cycloid constraint comprising: a tooth formed on one ofthe first jaw member and the second jaw member; and a notch formed onthe other of the first jaw member and the second jaw member.
 6. Therobotic system of claim 4, wherein the geared constraint comprises a pinwhich extends along an axis through the first jaw member and the secondjaw member, wherein the pin is configured to ride within a slot formedin at least one of the first jaw member and the second jaw member. 7.The robotic system of claim 1, further comprising a slot constraintconfigured to prevent or reduce a risk of rotation of the end effectorabout the first drive pin and the second drive pin when the first drivepin and the second drive pins are aligned.
 8. The robotic system ofclaim 7, wherein the slot constraint comprises: a first ear; a secondear spaced apart from the first ear to form a slot between the first earand the second ear; and a pin extending along the pulley axis positionedwithin the slot.
 9. The robotic system of claim 8, wherein the first earand the second ear are each coupled to the link.
 10. The robotic systemof claim 1, further comprising: a geared constraint configured toconstrain motion of the first jaw member and the second jaw member suchthat motion of one of the first jaw member and the second jaw membercauses a substantially corresponding motion of the other of the firstjaw member and the second jaw member; and a slot constraint configuredto prevent or reduce a risk of rotation of the end effector about thefirst drive pin and the second drive pin when the first drive pin andthe second drive pins are aligned.
 11. The robotic system of claim 1,wherein the first pulley and the second pulley can rotate to a positionin which the first drive pin and second drive pin are aligned.
 12. Therobotic system of claim 1, wherein, during rotation of the first pulleyand the second pulley, the first drive pin can rotate past the seconddrive pin.
 13. The robotic system of claim 1, wherein: the linkcomprises a housing comprising a first bearing surface spaced apart froma second bearing surface; the first jaw member comprises a first grooveconfigured to pivot on the first bearing surface to form the first pivotpoint; and the second jaw member comprises a second groove configured topivot on the second bearing surface to form the second pivot point. 14.The robotic system of claim 1, wherein the end effector is configured asa grasper, cutter, or clipper.
 15. The robotic system of claim 1,wherein: a first link comprises a first distance between the pulley axisand a point at which an input force is applied by a cable wound on thefirst pulley; a second link comprises a second distance between thepulley axis and an axis of the first drive pin; a third link comprises athird distance between the axis of the first drive pin and an axis ofthe first pivot point; a fourth link comprises a fourth distance betweenthe axis of the first pivot point and a distal end of the first jawmember.
 16. The robotic system of claim 15, wherein: the first distanceof the first link is between 3 and 4 mm; the second distance of thesecond link is between 2 and 3 mm; the third distance of the third linkis between 7 and 8 mm; and the fourth distance of the fourth link isbetween 17 and 23 mm.
 17. A robotic system comprising: a medicalinstrument including an end effector configured to be inserted into apatient during a medical procedure, the medical instrument comprising: afirst pulley; a first jaw member connected to the first pulley; a secondpulley; a second jaw member connected to the second pulley; a linkproviding a first pivot point about which the first jaw member can pivotand a second pivot point about which the second jaw member can pivot;and at least one of a geared constraint and a slot constraint.
 18. Thesystem of claim 17, wherein the end effector is connected to a roboticarm and controlled by a processor of the system.
 19. The system of claim17, further comprising: one or more cables connected to the firstpulley, wherein pulling one or more of the cables connected to the firstpulley causes rotation of the first pulley; and one or more cablesconnected to the second pulley, wherein pulling one or more cablesconnected to the second pulley causes rotation of the second pulley. 20.The system of claim 19, wherein: (i) the one or more of the cablesconnected to the first pulley and (ii) the one or more of the cablesconnected to the second pulley extend through the medical instrument;the medical instrument is attached to an instrument drive mechanism; andthe instrument drive mechanism is configured to pull (i) the one or moreof the cables connected to the first pulley and (ii) the one or more ofthe cables connected to the second pulley to actuate the end effector.